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NEWS | May 25, 2017

Executive Summary of the Investigation of the Alleged Civilian Casualty Incident in the al Jadidah District, Mosul

By BG Matthew C. Isler

IRIZ-DCA                                                                                                                                                                                                                8 May 2017

MEMORANDUM FOR Commander , Combined Joint Forces Land Component Command-Operation Inherent Resolve, Union Ill, Baghdad, Iraq, APO AE 09548

SUBJECT: Executive Summary of Army Regulation 15-6 Investigation of the Alleged Civilian Mass Casualty Incident in the al Jadidah District, City of Mosul, Ninewah Governate, on or about 17 March 2017

1. Conclusion. At 0824 on 17 March 2017, Coalition aircraft conducted an airstrike against two ISIS snipers engaging the Iraqi Counter Terrorism Service (CTS). Coalition Forces conducted the strike in accordance with the applicable Rules of Engagement and the Law of Armed Conflict (LOAC). Coalition aircraft employed a single GBU-38 precision-guided munition. The weapon appropriately balanced the military necessity of neutralizing the snipers with the potential for collateral damage. The GBU-38 entered the roof and detonated in the second floor of the structure.

    a. The GBU-38's detonation ignited ISIS explosive materials that ISIS had previously emplaced in the structure. The secondary explosion triggered a rapid failure of the structure, killing the two ISIS snipers and 101 civilians sheltered in the bottom floors of the structure. An additional four civilians were killed in the neighboring structure to the west.

    b. Eye witnesses and media outlets reported that an additional 36 civilians may have been at the building; however, there is insufficient evidence to determine their status or whereabouts at this time.

     c. The Target Engagement Authority (TEA) was unaware of and could not have predicted the presence of civilians in the structure prior to the engagement.

2. Operational Context. At the time of the strike, CTS forces were engaged in offensive maneuver to seize the sector from 35-40 ISIS fighters controlling the area. On 17 March 2017, CTS had been postured along the same Forward Line of Troops (FLOT) for three days. That day was also the first day of the planned CTS advance into a new sector of the al Jadidah district. CTS Soldiers had continuous over-watch of the sector during this period, including direct visual observation (VISOBS) of the structure.

3. Enemy Activity. Coalition Intelligence , Surveillance, and Reconnaissance (ISR) and CTS forces observed ISIS fighters forcibly evict civilian families from the area, build defensive fighting positions, stage vehicle-borne improvised explosive devices (VBIEDS), emplace improvised explosive devices (IEDs), and engage CTS forces with direct and indirect fire. Coalition and Iraqi human intelligence as well as Coalition multi• source intelligence overwhelmingly classified the district as ISIS-controlled and specifically prepared to deny the CTS advance north.

    a. In the days prior to 17 March 2017, ISIS fighters conducted complex attacks against the CTS FLOT. CTS had defended against ISIS VBIEDS and suicide bombers on multiple occasions each day. During this period, CTS forces, with Coalition support , conducted a combined-arms defense to protect CTS Soldiers.

    b. The testimony of multiple residents confirms that ISIS fighters knocked holes into the walls. The "wormholes " allowed ISIS to move fighters, weapons , and equipment between buildings without being detected by Coalition ISR or CTS visual observers .

4. Civilians. Coalition ISR observed , and civilian testimony confirmed, that ISIS fighters forcibly expelled families from their homes in the district. The displaced civilians were invited by a well-known neighbor to seek refuge in his home. It is estimated that between 101 and 137 civilians voluntarily sought refuge in the lower two floors of the structure.

    a. Counter Terrorism Service (CTS) VISOBs and Coalition intelligence assets did not observe the civilians enter or use the structure. Neither Coalition nor CTS forces knew that civilians were sheltered within.

    b. The ISIS fighters , however , knew of the civilians' presence within the structure , and interacted with the civilians. According to the next-door neighbor's testimony, ISIS fighters had issued a warning to him that his family was in danger. ISIS fighters advised him to evacuate his family from their residence and move north by the morning of 17 March 2017. ISIS warned him that , if the fam ily remained, what would happen to them was not ISIS' fault.

5. Strike. CTS forces initiated their assault to seize and clear of the sector at approximately 0700L on the morning of 17 March 2017. CTS visual observers did not identify any civilians within the sector prior to the strike.

    a. During their assault, CTS visual observers identified two ISIS snipers effectively engaging CTS soldiers from a Defensive Fighting Position (DFP) in the southwest corner of the second story of the structure. Iraqi CTS Battalion and Brigade commanders approved the observer request for a Coalition strike on the DFP and coordinated with an Iraqi Forward Air Controller (IFAC) to prepare a strike request. The IFAC coordinated with Coalition Advisors to plan the strike.

    b. After receiving the strike request, the Coalition Strike Cell in Erbil, a joint fires and control center under the command of a Coalition Target Engagement Authority (TEA), evaluated intelligence on enemy activities and forces in the area surrounding the DFP location. The Strike Cell staff also evaluated the location of the target with regard to historical civilian population reporting and the location's proximity of friendly forces . Weaponeering experts analyzed available weapons and selected a weapon and fusing option that would achieved the necessary effect and minimize collateral damage.

     c. The TEA positively identified the ISIS snipers and determined that the engagement was authorized under the Rules of Engagement (ROE). As a weaponeering solution, the TEA selected a GBU-38 with a delayed fuse.

    d. The TEA approved the engagement on the ISIS snipers. The engagement was the sixth of 81 weapons engagements that Coalition forces conducted in support of the CTS operations that day. After the weapon detonated, CTS visual observers reported that the DFP was destroyed.

6. Law of Armed Conflict. The TEA approved the strike in accordance with all provisions of the applicable ROE and Law of Armed Conflict (LOAC) .

    a. Distinction. The Coalition attacked a valid military target which consisted of two snipers effectively engaging Iraqi CTS soldiers from a DFP.

    b. Proportionality. The TEA selected a weapon that balanced the military necessity of neutralizing the two snipers with the potential for collateral damage to civilians and civilian structures.

           (1) The TEA selected a GBU-38, a 500-pound class precision guided munition containing 1921bs of explosive material. The GBU-38's steel case was strong enough to penetrate the roof of the DFP and had sufficient explosive material to neutralize the snipers engaging the CTS soldiers from their DFP in the second floor. The TEA selected a fuse-setting that would neutralize the threat to CTS, while also minimizing risk to collateral structures. The TEA expected the weapons effects for the GBU-38 to be localized to the second floor of the building. Subsequent engineering and weapons analysis indicates that the GBU-38 should have resulted in no more than 16-20% damage to the structure , localized to the front of the second floor or the structure.

           (2) The TEA did not know civilians were in the structure or that ISIS had deliberately staged a significant amount of secondary explosive materials in the structure. Based on the information reasonably available , the TEA could not have predicted the compounded effects of the secondary explosives emplaced by ISIS fighters .

     c. Military Necessity. CTS commanders and the TEA determined that it was a military necessity to neutralize the ISIS snipers in order for CTS to achieve its maneuver objective of seizing the sector from ISIS. If the ISIS snipers were left to continue to engage CTS forces , CTS would incur unacceptable levels of casualties in the seizure of the sector. The seizure of the sector was necessary for CTS to complete the clearance and liberation of Mosul from ISIS.

7. Damage Resulting from the Enqaqement. The GBU-38 entered the northern portion of the roof at the front/north of the structure at a near-vertical angle. The GBU-38 detonated while penetrating the roof above the second floor of the structure . The GBU- 38 sparked a secondary detonation of a large amount of explosive material that ISIS had previously emplaced in the structure. The secondary explosion produced a powerful blast and overpressure that triggered a rapid progressive failure of the structure. These events killed the two ISIS snipers, 101 civilians sheltered in the bottom floors of the structure, and four civilians in the neighboring structure to the west. Eye witnesses and media reported that an additional 36 individuals may have been located within the structure at the time of the engagement. However, the status of these individuals is undetermined at this time.

8. Post-Blast Analysis . Post-blast analysis conducted by a Coalition Explosive Ordnance Disposal (EOD) team identified explosive residues not consistent with the explosive content of a GBU-38 from several sample locations around the site, including Pentaerythritol Tetranitrate (PETN) and nitroglycerin.

    a. The senior EOD officer concluded that the PETN was associated with improvised explosive devices or detonator cord (known as "DetCord"), a common explosive component which ISIS uses to link together larger explosive devices for simultaneous detonation. Furthermore, nitroglycerin residue also indicated the presence of secondary explosive devices, and was likely used by ISIS to sensitize the secondary explosive devices to detonate more easily. Finally, post-blast analysis conducted by EOD and expert weapons teams concluded that the structural damage and crater at the rear/south of the structure were not caused by the relatively low explosive weight of a single GBU-38.

    b. The location of the structural damage and the crater at the rear/south of the structure were displaced from the site of the GBU-38 entry and blast, and far in excess to what could have been caused by the GBU-38's net explosive weight. Instead, the structural damage and crater were likely caused by a large amount of ISIS-emplaced explosive material located in the second story of the rear of the structure. This ISIS• emplaced explosive material conservatively contained more than four times the net explosive weight of the GBU-38. The sympathetic detonation of this secondary ISIS• emplaced explosive, activated by the GBU-38 impact, collapsed the structure, resulting in the vast majority of the 101 civilian casualties, and impacted the neighboring structure which resulted in four additional civilian casualties.

9. The point of contact for this memorandum is the undersigned.

                                                                                                                                               ///ORIGINAL SIGNED///
                                                                                                                                               Matthew C. Isler 
                                                                                                                                               Brigadier General, U.S. Air Force 
                                                                                                                                               Investigating Officer