Cluster Munitions and ERW in Lebanon

by Daniele Ressler and Elizabeth Wise [Mine Action Information Center]

The recent 34-day conflict between the Lebanese armed faction Hezbollah and Israel from July 12 to August 14, 2006, saw extensive use of surface-launched munitions and air-dropped munitions (to a lesser degree), resulting in wartime casualties for military and civilian actors in both Lebanon and Israel. Since the ceasefire agreement, international post-conflict attention has become focused on Lebanon due to the large amount of explosive remnants of war left behind after the conflict. In particular, cluster munitions are proving problematic for post-conflict reconstruction activities in Lebanon due to their apparent high failure rate1 and the potential threat they pose to returning civilians, aid workers and military personnel. This article examines cluster munitions and the impact of their presence in Lebanon.

Early cluster munitions were used in World War II and were later deployed extensively by U.S. forces in Southeast Asia during the American/Vietnam War. Millions of tons of cluster submunitions were dropped on Laos, Cambodia and Vietnam—90 million on Laos alone.2 Cluster munitions were further used extensively during the Gulf War of 1991 (by the United States and allies), in Kosovo and Yugoslavia in 1999 (United States, United Kingdom and Netherlands), Afghanistan in 2001–2002 (United States) and Iraq in 2003 (United States and United Kingdom).

A cluster weapon consists of a munitions container deployed by a weapon-delivery system such as a bomb dropped by aircraft, rocket launcher or artillery projectile, which then releases smaller munitions in mid-air that are spread over a particular area. These smaller munitions, or submunitions, are designed to explode on impact or close to the time of impact. Typically the delivery systems are designed to carry and deploy hundreds of submunitions at a time. Submunitions are also called bomblets, bombies, BLUs (bomb live units) or grenades.

Cluster munitions can be delivered by air or surface. Air-dropped cluster dispensers (or cluster bomb units) are released or fired from airplanes, and after a specified amount of time or distance, the dispenser opens to allow submunitions to effectively cover a wide target area. With the exception of sensor-fuzed weapons, CBUs all fall into the "dumb bomb" or unguided category, meaning once released, their trajectory cannot be controlled or re-directed.3 Surface-launched munitions are delivered by artillery launchers on the ground that are fired over a long range to detonate either in the air or on impact. In the case of cluster munitions, each dispenser (e.g., missile, rocket, projectile) carries a payload of submunitions that is released after the dispenser is in flight, to drop over the target area.

Image 4
Various types of ordnance that the United Nations has collected in southern Lebanon in its efforts to clear the region of landmines, unexploded missiles and cluster bombs. Unexploded cluster submunitions are reportedly being found in high numbers in southern Lebanon, indicating a high failure rate of some of these munitions when used during the 2006 conflict (see sidebar). Photo courtesy of AP/Alfred de Montesquiou
Image 2
A United Nations Chinese battalion involved in demining the town of Hiniyah in Lebanon prepares to detonate unexploded ordnance. The soldiers locate the unexploded devices, remove and relocate them to a safe area, and then detonate them. Photo courtesy of UN/Mark Garten

During a conflict, cluster weapons are used by the military for attacking an area where the target may be moving, such as a military convoy, either to attack and destroy the enemy by dropping explosive bomblets (impact) or to prevent or slow enemy movement from or to an area by dropping devices which essentially function as landmines (area denial).3 It is important to note that submunitions are different and not all are explosive or harmful in the way that is properly understood; for example, area denial submunitions do not explode but are victim-activated and classified as landmines.4 For the purpose of this article, the submunitions discussed are understood to be those meant to explode on impact.

The area a single cluster munition can cover with submunitions is known as a footprint, and depending on the delivery system and type of weapon, one cluster munition salvo may strike an area as large as one square kilometer (247 acres).1 Cluster munitions are useful to a military because the size of the cluster-munition footprint is much larger than that of a single bomb.

Because there are many kinds of cluster munitions and bomblets with different abilities and uses, a convoluted understanding of these weapons can occur. For example, an MLRS rocket salvo is capable of releasing thousands of submunitions over an area within a one-kilometer (0.6-mile) radius,5 but most other strikes have fewer submunitions and a far smaller area of impact.4 Upon impact, deadly shrapnel from each submunition can be projected over a radius of up to 50 meters (55 yards) from the largest bomblets dropped by air;1 however, most of the submunitions found in Lebanon and discussed in this article have a fragmentation radius of less than 10 meters (33 feet).

While in no way intending to undermine the potential threat of cluster munitions both during and after conflict, it is important to examine cluster munitions and their submunitions individually rather than grouping them together and making generalized assumptions. This is particularly true as international attention has recently focused on cluster munitions and is discussing their potential regulation or prohibition based on the potential threat submunitions may pose to militaries and civilians during and after use.

Controversy about Cluster Munitions

The dud rate for cluster submunitions varies dramatically; reported failure rates can typically range anywhere from under 2 percent to over 30 percent.6 The potentially high failure rate of some cluster submunitions is one reason they are controversial. The range in failure rate is extreme in part because different types of cluster munitions and their parts vary greatly, particularly the fuzes, resulting in varying levels of successful design. In fact, not all cluster munitions have an unacceptably high failure rate; for example, while faulty fuzes can be a reason munitions fail to explode, some fuzes are extremely reliable in their design.7

Even testing and reporting failure rates is problematic because there may be a difference between the failure rate in ideal testing conditions and combat conditions.8 In official testing, submunitions may be dropped on hard surfaces without obstructions such as vegetation, leading to lower failure-rate statistics than are reflected in real conditions.8, 9

Since conditions in the field are not necessarily the same as those during testing, in some cases cluster submunitions may have significantly higher failure rates during use. Failure-rate statistics based on field use, however, typically can only be derived from anecdotal or incomplete records taken during the conflict and are therefore harder to rigorously document and prove.9, 10 Thus, failure rates quoted for cluster submunitions may be underestimated if based on an ideal testing environment and may be unreliable or over-estimated if based on spotty in-conflict data.

Reasons for a high failure rate vary and can depend on the age of the submunition; storage conditions; production (design, construction, quality of fuzes); deployment (arming and delivery technique, altitude of delivery); or landing (angle of impact; softness and slope of terrain; vegetation such as trees or bushes, marshes, snow or water, and extreme heat or cold).6, 9

Cluster munitions are often delivered as "unguided bombs," meaning that they can be aimed, but once fired, there is no controlling exactly where they land. This results in a higher probability that they may miss the intended military target and hit civilian areas. Factors such as weapon design, altitude at which the dispenser is dropped or opens, wind, dispenser spin rate and the slope of the ground can all affect the size and location of a cluster bomb's footprint, contributing to potentially inaccurate dispersal, unpredictable results and undocumented locations of subsequent unexploded submunitions.10

With these concerns in mind, Human Rights Watch has been developing a list of the "worst offender" cluster munition weapons they consider to be particularly inaccurate and unreliable. In 2003 (during the Iraq war), HRW called on the United States and other countries to halt the production, use and sale of four such munitions: the CBU-99/CBU-100 containing Rockeyes; the CBU-87/B with the BLU 97 Combined Effects Munition; 155-mm Dual Purpose Improved Conventional Munition artillery projectiles with M42 and M46 submunitions; and Multiple Launch Rocket Systems with M26 warheads (containing M77 bomblets).11 Recently HRW expanded their list, which now totals 12—a "dirty dozen"—cluster munitions.12

Recent Cluster-munition Use in Lebanon

Before the recent conflict in Lebanon involving Hezbollah, Israel used cluster munitions in its 1978 and 1982 incursions into Lebanon.13 The two-decade-old unexploded submunitions from Israeli campaigns have continued killing and injuring civilians, with over 200 civilian casualties recorded between 2000 and 2005. To be fair, it must be understood these casualties include both landmines and UXO; however, after these (and other) conflicts, clearance teams have found at least six confirmed types of unexploded cluster submunitions contributing to Lebanese civilian casualties.14

It is for this reason that Human Rights Watch and others expressed concern when it was reported that Israel was using cluster munitions in Lebanon in the recent conflict: first reportedly on July 19, 2006, in the town of Blida15 and then in numerous strikes across the country with accelerated use during the last 72 hours of the conflict.16 The United Nations estimates the Israeli Defense Forces fired up to 6,000 bombs, rockets and artillery a day into Lebanon.17

Now several months after the ceasefire, the United Nations and clearance groups are continuing to collect data to understand the implications of the conflict. The United Nations initially estimated there may be as many as one million unexploded cluster submunitions in Lebanon resulting from an exceptionally high overall failure rate of about 40 percent for the cluster submunitions fired or dropped in Lebanon during the conflict.18 U.N. and Lebanese demining teams have found 770 cluster munition strike locations as of October 10, and this number will continue to grow as the search continues.19

Reports made shortly after the end of the conflict documented initial findings of unexploded cluster submunitions on the ground in Lebanon, including M42s, M46s, three variations of M85s, M77s and BLU-63s.4, 18, 20, 21 Notably, all four of the cluster munitions dispersing these submunitions are included in Human Rights Watch's "dirty dozen" list, meaning the primary cluster munitions used in Lebanon are reported to potentially be among the most inaccurate and unreliable.12

The cluster submunitions dispersed in Lebanon appear to have been delivered most extensively via artillery projectiles, followed by Multiple Launch Rocket Systems and less so by aerial cluster bombs.20 It is likely that additional cluster submunitions will be found during ongoing clearance in Lebanon but these types, delivered by surface and air, are discussed in the sidebar. The United Nations also noted that in addition to cluster munitions in Lebanon, there are an estimated 15,300 items of unexploded ordnance including air-dropped bombs of 500 to 2,000 pounds (200 to 900 kilograms), ground- and naval-launched artillery rounds, and air-delivered rockets.17

Human Rights Watch released an unconfirmed report October 19 that stated Hezbollah fired a type of Chinese cluster munition into Israel as well during the conflict (see sidebar).22

Effect on Civilians in Lebanon

When cluster munitions are dropped, the bomblets can be spread intentionally or unintentionally over a large area. The Multiple Launch Rocket System, for example, is believed to have a margin of error of up to three-quarters of a mile (1.2 kilometers) from the intended target.23 Because of the imprecision of these rockets, an army may "flood" a battlefield with submunitions in order to increase the chance of striking the intended target.23

Unexploded cluster submunitions can in some cases be extremely unstable and unreliable. While some submunitions may be moved successfully without detonation depending on how they landed and the cause of failure, others may explode with even a touch. Older unexploded submunitions dropped in Lebanon such as BLU-63 bomblets may be more unreliable or unstable with age;24 additionally, small submunitions such as MLRS-delivered M77 bomblets can be hard to see until it is too late (see sidebar for information on both). In this way, some consider cluster bomblets with high failure rates to become de facto anti-personnel landmines.

Colin King, international landmine and explosive ordnance disposal consultant, notes that unexploded cluster bomblets are dangerous in part because their condition is unknown: they might be fully armed and ready to detonate, not armed and relatively harmless, or partially armed. If they are armed, they may or not be capable of firing, adding to their unpredictability One important challenge according to King is not only to clear the submunitions in Lebanon safely, but to further study what condition they were found in and why they failed to arm and explode.4

As of October 8, 2006 there have been 20 reported fatalities and 120 reported injuries from UXO in Lebanon, in nearly all cases from cluster submunitions.25, 26 Four of these fatalities and 42 of the injuries were children 18 years old or younger.25

The United Nations has estimated it may take 12 to 15 months to clear most of the cluster submunitions and other UXO in Lebanon.19 Because of the large footprints of cluster bombs, for each strike location clearance personnel must verify an area totaling 196,000 square meters (48.5 acres) to locate and destroy all unexploded submunitions.19 The United Nations reported that as of September 26, over 350 Lebanese Army personnel along with some 200 nongovernmental organization and commercial company personnel were working on clearance under the management of the United Nations Mine Action Coordination Centre of South Lebanon and Lebanon's National Demining Office, with additional clearance coming from United Nations Interim Force in Lebanon troops.26 More than 45,000 submunitions had been cleared by these operators as of October 10, 2006.19

Legality and Future of Cluster Munitions

The use of cluster munitions is not currently prohibited under international humanitarian law. However, part of IHL prohibits indiscriminate attacks, "which employ a method or means of combat which cannot be directed at a specific military objective."27 Additionally, IHL prohibits disproportionate attacks, or any that "may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof, which would be excessive in relation to the concrete and direct military advantage anticipated."27

Israel claims its use of cluster bombs in Lebanon complies with international law. An Israeli military spokesman told Reuters news agency, "Everything the Israeli Defence Forces are using is legitimate."28 Some disagree, arguing as Ken Roth from Human Rights Watch does, that "the use of cluster munitions in or near civilian areas violates the ban on indiscriminate attacks, because these weapons cannot be directed at only military targets."29

The tension over cluster-munition use is an intersection of humanitarian concerns and military interests. This is reflected in debates over the future of cluster munitions. Some nongovernmental organizations—notably the Mennonite Central Committee—have long been advocating for a total ban on cluster munitions.24 Other NGOs have called for a moratorium on use, production or trade of cluster munitions until humanitarian concerns can be addressed; this is the position of the Cluster Munitions Coalition, created in 2003 and now with over 150 member NGOs.30

Rather than prohibiting use, some militaries have instead started taking a technological response to cluster munitions, creating weapons with lower failure rates, improved accuracy, self-destruct/self-neutralizing mechanisms or back-up secondary fuzes.10 Rather than stop using them, the goal is to increase reliability. Not all militaries support this, with poorer ones, such as Russia and China, arguing they cannot afford such an approach.24 Yet improvements to cluster munitions are supported by many within the military who have experienced the danger of fratricide to ground troops by unexploded submunitions deployed by their own military.

The U.S. Department of Defense's 2006 proposed military spending budget requested funding to update outdated cluster munitions.31 Updating cluster munitions would potentially improve targeting and the dud rate. The Army requested $124.8 million to purchase 1,026 Guided Multiple Launch Rocket System munitions.31 The GMLRS claims to reduce the dud rate of the current MLRS by 95 percent and the impact area by 85 percent.31 These new munitions aim to solve many of the problems of the older cluster munitions: indiscriminant effects, high dud rates and attacks on civilians.


The Mennonite Central Committee has used the phrase "drop today, kill tomorrow" to describe the danger cluster munition UXO can pose for civilians.32 This is clearly the case in post-conflict Lebanon, where unexploded cluster submunitions are already killing civilians. However, not all cluster munitions are created equal, and this issue is complex. The debate continues with some defending the use of cluster munitions, others advocating for improvements in technology or stronger legal regulation and still others decrying any use at all. What is undeniable is that cluster submunition duds have resulted in explosive remnants of war that continue to injure innocent civilians. There may be more than one solution to the problem of cluster munitions, but it demands an answer and should not be ignored.

USA Today produced an excellent video special report, "Steel Rain: The Use of Cluster Weapons in Iraq," about cluster munitions. For more information on how they work and the problems they cause, visit:

Special thanks to Colin King for his assistance in providing information for parts of this article.


HeadshotDaniele Ressler works as a Researcher, Writer and Assistant Editor for the Journal of Mine Action. She holds a Master of Science in violence, conflict and development studies from the University of London's School of Oriental and African Studies. She has studied in Switzerland as well, earning a Certificate for Applied Studies in peacemaking. Daniele has previously worked in Washington, D.C., and Seattle, Washington, in the field of conflict management, and has lived in Nairobi, Kenya.

HeadshotElizabeth Wise was an Editorial Assistant with the Journal of Mine Action from May to August 2006. She holds a Bachelor of Arts in English and is currently pursuing a Master of Arts in technical and scientific communication at James Madison University.


  1. Also known as the dud rate, the failure rate is "the percentage of submunitions in each canister that fail to explode," from "Technical Analysis." Cluster Munition Coalition. Accessed September 4, 2006.
  2. Collins, Robin. "The Emerging Campaign Against Cluster Bombs and Explosive Remnants of War." The Ploughshares Monitor. Autumn 2002, vol. 23, no.3. Accessed September 13, 2006.
  3. "Cluster Bombs." Accessed August 22, 2006.
  4. Interviews by Daniele Ressler with Colin King, international landmine and explosive ordnance disposal consultant and owner of C. King Associates Ltd., on November 3, 2006, via phone and November 6, 2006, via email.
  5. "Cluster Munition Questions and Answers: The M26 Rocket." Human Rights Watch. August 18, 2006. Accessed August 21, 2006.
  6. "A Global Overview of Explosive Submunitions: Memorandum to CCW Delegates." Human Rights Watch. May 21, 2002. Accessed September 5, 2006.
  7. One example of a reliable fuse is the AO-1SCh fuse. King, Colin. "Explosive Remnants of War: Submunitions and Other Unexploded Ordnance: A Study." International Committee of the Red Cross. August 2000: Geneva.
  8. Hiznay, Mark. "Operational and Technical Aspects of Cluster Munitions." Disarmament Forum: Cluster Munitions. 2006, vol. 4, p.15–26. Accessed October 20, 2006.
  9. McGrath, Rae. "Cluster Bombs: The Military Effectiveness and Impact on Civilians of Cluster Munitions." UK Working Group on Landmines. September 2000, p.58. Accessed September 17, 2006.
  10. "Clusters of Death: Chapter 1." Mennonite Central Committee. Accessed February 12, 2007.
  11. "Cluster Munitions a Foreseeable Hazard in Iraq." Human Rights Watch. March 18, 2003. Accessed September 13, 2006.
  12. "Overview of a Dirty Dozen Cluster Munitions." Human Rights Watch. Updated August 26, 2006. Accessed September 15, 2006.
  13. "Cluster Munitions in Lebanon." Landmine Action. Updated 2005. Accessed September 25, 2006.
  14. "The Mine Problem, Southern Lebanon." Mine Action Coordination Centre of South Lebanon. Accessed October 16, 2006.
  15. "Israeli Cluster Munitions Hit Civilians in Lebanon." Human Rights Watch. July 24, 2006. Accessed September 22, 2006.
  16. Shadid, Anthony. "In Lebanon, a War's Lethal Harvest. Threat of Unexploded Bombs Paralyzes the South." Washington Post. September 26, 2006. Accessed October 25, 2006.
  17. "'Million Bomblets' in S. Lebanon." BBC News. September 26, 2006. Accessed September 27, 2006.
  18. "Situation Report and Operations Update." Mine Action Coordination Centre of South Lebanon. September 14, 2006. Accessed October 16, 2006.
  19. "South Lebanon Cluster Bomb Info Sheet." Mine Action Coordination Centre of South Lebanon. October 10, 2006. Accessed October 13, 2006.
  20. Goose, Steve. "Convention on Conventional Weapons (CCW): First Look at Israel's Use of Cluster Munitions in Lebanon in July–August 2006." Human Rights Watch. Briefing delivered at the Fifteenth Meeting of the Group of Governmental Experts, August 30, 2006: Geneva. Accessed September 12, 2006.
  21. Cloud, David. "Inquiry Opened Into Israeli Use of U.S. Bombs." New York Times. August 24, 2006. Accessed August 25, 2006.
  22. "Lebanon/Israel: Hezbollah Hit Israel with Cluster Munitions During Conflict. First Confirmed Use of Weapon." Human Rights Watch. October 19, 2006. Accessed October 20, 2006.
  23. Rappaport, Meron. "IDF Commander: We Fired More than A Million Cluster Bombs in Lebanon." Haaretz. September 12, 2006. Accessed September 14, 2006.
  24. Goose, Steve. "Cluster Munitions: Toward a Global Solution." Human Rights Watch. January 26, 2004. Accessed August 16, 2006.
  25. "Casualties as of October 8, 2006." Mine Action Coordination Centre of South Lebanon. October 8, 2006. Accessed October 13, 2006.
  26. "Lebanon Response OCHA Situation Report No. 39." United Nations Office for the Coordination of Humanitarian Affairs. September 27, 2006. Accessed September 27, 2006.
  27. "Israel and Hizbullah Must Spare Civilians: Obligations Under International Humanitarian Law of the Parties to the Conflict in Israel and Lebanon." Amnesty International USA. Accessed September 6, 2006.
  28. "Israel Urged to Shun Cluster Bomb." BBC News. July 25, 2006. Accessed August 18, 2006.
  29. "Lebanon: Israeli Cluster Munitions Threaten Civilians." Reuters Alertnet. August 17, 2006. Accessed February 12, 2007.
  30. The Cluster Munition Coalition. Accessed September 1, 2006.
  31. "Department of Defense Procurement Requests." Human Rights Watch. July 2005. Accessed August 8, 2006.
  32. Wiebe, Virgil and Titus Peachey. "Drop Today, Kill Tomorrow: Cluster Munitions as Inhumane and Indiscriminate Weapons." Mennonite Central Committee. December 1997. Revised June 1999. Accessed February 12, 2007.
  33. "Dual-Purpose Improved Conventional Munitions." Accessed September. 7, 2006.
  34. "M483, 155-mm Howitzer Shell." Updated April 27, 2005. Accessed August 16, 2006.
  35. "Cargo Ammunition: 155mm." Israel Military Industries, Ltd. Accessed September 15, 2006.
  36. "M85 Dual-purpose Bomblet." Updated April 27, 2005. Accessed September 15, 2006.
  37. USA Today Interactive Flash Presentation. Found in: Wiseman, Paul. "Cluster Bombs Kill in Iraq, Even After Shooting Ends." USA Today. December 16, 2003. Accessed September 15, 2006.
  38. "Questions and Answers: 122mm Cluster Munition Rockets." Human Rights Watch. October 18, 2006. Accessed February 12, 2007.
  39. "CBU-58." Federation of American Scientists: Military Analysis Network. Updated February 5, 1998. Accessed August 16, 2006.
  40. "CBU-52B/B; CBU-58B, A/B; and CBU-71/B, A/B." Vipers in the Storm: Weapons Bunker. Last updated 2003. Accessed November 9, 2006.


  1. "Cluster Bombs." Mennonite Central Committee. Accessed August 8, 2006.
  2. "Failure to Protect: A Case for the Prohibition of Cluster Munitions." Landmine Action. August 2006. Accessed August 30, 2006.
  3. "International Humanitarian Law Relevant to Cluster Munitions." Cluster Munition Coalition. Accessed August 21, 2006.
  4. "Off Target: the Conduct of the War and Civilian Casualties in Iraq, Chapter IV." Human Rights Watch. December 12, 2003. Accessed August 20, 2006.
  5. "What is a Cluster Bomb?" Handicap International. Accessed August 20, 2006.

Contact Information

Daniele Ressler, MSc
Researcher/Assistant Editor
Journal of Mine Action
Mine Action Information Center

Elizabeth Wise
Editorial Assistant
Journal of Mine Action

Colin King
C King Associates, LTD
Wych Warren
Forest Row
East Sussex RH18 5LP / UK
Tel: +44 1342 826 363
Fax: +44 1342 825 961
Web site: