WASHINGTON — The United States has killed 119 civilians in Iraq and Syria since it began military operations against the Islamic State there in 2014, military officials said Wednesday. 
 
 In each case, the American military followed the proper procedures and it did not violate laws of armed conflict, officials said. 
 
 “Significant precautions were taken, despite the unfortunate outcome,” said Col. John J. Thomas, a spokesman for United States Central Command, which oversees American military operations in Iraq, Syria and elsewhere in the Middle East. 
 
 “In most every case, when we determined there may have been civilian casualties from one of our airstrikes, we are choosing to list the largest number of possible civilian casualties,” he said. “In cases where we just don’t have the investigative resources or evidence to determine precisely how many people may have died, we went with the worst-case number to ensure a full accounting.” 
 
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 Human rights activists over the summer accused the United States of killing scores of civilians during operations against the Islamic State, also known as ISIS or ISIL, in northern Syria. Around the same time, Central Command put in place a new process for examining allegations that its strikes had caused civilian casualties. 
 
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 As part of that review, the military investigated 257 allegations of civilian casualties and deemed 31 of them credible, according to military officials. 

 From a U.S. Central Command News Release 
 
 TAMPA, Fla., Nov. 9, 2016 — After months of reviewing reports and databases to resolve cases in which coalition airstrikes may have resulted in civilian casualties, U.S. Central Command officials have determined that over the past year, 24 U.S. airstrikes targeting the Islamic State of Iraq and the Levant may have killed as many as 64 civilians and injured eight others in Iraq and Syria. 
 
 "We have teams who work full-time to prevent unintended civilian casualties," Centcom spokesman Air Force Col. John J. Thomas said. 
 
 A key tenet of the counter-ISIL air campaign is to avoid adding to the tragedy of the situation by inflicting additional suffering, the colonel said. 
 
 “Sometimes civilians bear the brunt of military action,” he added, “but we do all we can to minimize those occurrences, even at the cost of sometimes missing the chance to strike valid targets in real time.” 
 
 Thorough Review 
 
 Centcom thoroughly reviewed the facts and circumstances surrounding each report, officials said. 
 
 "The assessments determined that in each of these strikes, the right processes were followed,” Thomas said. “Each complied with Law of Armed Conflict, and significant precautions were taken, despite the unfortunate outcome." 
 
 Centcom officials said the investigations were informed by the military's own records, combined with an exhaustive review of reports from outside sources from news media reports, nongovernmental organizations and other U.S. government departments and agencies. 
 
 Thomas said the numbers of casualties associated with each individual airstrike reflect the highest possible total possible, according to the assessment. 
 
 "In most every case, when we determined there may have been civilian casualties from one of our airstrikes, we are choosing to list the largest number of possible civilian casualties,” he said. “In cases where we just don't have the investigative resources or evidence to determine precisely how many people may have died, we went with the worst-case number to ensure a full accounting." 
 
 List of Reviewed Airstrikes 
 
 Here are the 24 airstrikes officials reviewed, along with the casualty assessments: 
 
 -- In a Nov. 20, 2015, strike against an ISIL tactical unit near Dayr Az Zawr, Syria, officials assessed that five civilians were killed and three individuals were injured after the civilians entered the target area after the aircraft released its weapon. 
 
 -- In a March 5, 2016, strike against an ISIL weapons production facility near Mosul, Iraq, it is assessed that 10 civilians were killed. 
 
 -- In a March 24, 2016, strike against an ISIL target near Qayyarah, Iraq, it is assessed that one civilian was killed. 
 
 -- In an April 1, 2016, strike against ISIL tactical unit near Raqqah, Syria, it is assessed that three civilians were killed after entering the target area after the aircraft released its weapon. 
 
 -- In an April 9, 2016, strike against an ISIL tactical unit near Mosul, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 -- In an April 30, 2016, strike against ISIL military leadership near Mosul, it is assessed that five civilians were killed after entering the target area after the aircraft released its weapon. 
 
 -- In a May 25, 2016, strike against an ISIL tactical unit near Mosul, it is assessed that one civilian was killed. 
 
 -- In a May 26, 2016, strike against ISIL fighters near Mosul, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 -- In a May 29, 2016, strike against an ISIL weapons system near Mosul, it is assessed that six civilians were killed. 
 
 -- In a June 15, 2016, strike against an ISIL weapons storage facility near Kisik, Iraq, it is assessed that six civilians were killed. 
 
 -- In a June 15, 2016, strike against ISIL targets near Mosul, it is assessed that two individuals were injured after entering the target area after the aircraft released its weapon. 
 
 -- In a June 21, 2016, strike targeting an ISIL headquarters building near Raqqah, it is assessed that three individuals were killed after entering the target area after the aircraft released its weapon. 
 
 -- In a June 23, 2016, strike against an ISIL-held building near Raqqah, it is assessed that four civilians were killed after entering the target area after the aircraft released its weapon. 
 
 -- In a June 26, 2016, strike against an ISIL target near Mosul, it is assessed that one individual was injured after entering the target area after the aircraft released its weapon. 
 
 -- In a June 26, 2016, strike against an ISIL target near Mosul, it is assessed that one individual was injured after entering the target area after the aircraft released its weapon. 
 
 -- In a July 3, 2016, strike against an ISIL fighting position near Manbij, Syria, it is assessed that four civilians were killed. 
 
 -- In a July 10, 2016, strike against an ISIL target near Manbij, it is assessed that two civilians were killed. 
 
 -- In a July 14, 2016, strike on an ISIL-held building near Qayyarah, it is assessed that one civilian was killed. 
 
 -- In a July 31, 2016, strike against ISIL fighters near Manbij, it is assessed that one civilian was injured after entering the target area after the aircraft released its weapon. 
 
 -- In an Aug. 17, 2016, strike against an ISIL target near Raqqah, it is assessed that two civilians were killed. 
 
 -- In an Aug. 20, 2016, strike against an ISIL artillery firing position near Manbij, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 -- In an Aug. 31, 2016, strike against an ISIL target near Ramadi, Iraq, it is assessed that two civilians were killed. 
 
 -- In a Sept. 7, 2016, strike against an ISIL oil collection point near Dayz Az Zawr, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 -- In a Sept. 10, 2016, strike against an ISIL target near Raqqah, it is assessed that five civilians were killed. 

 
 
 An airstrike in Bashiqa, northern Iraq, on Tuesday. (Odd Andersen/Agence France-Presse via Getty Images) 
 
 The number of civilians killed by U.S. airstrikes in Iraq and Syria is more than double the previous estimate, U.S. Central Command said on Wednesday, after reexamining its air campaign based on allegations from activist groups. 
 
 The announcement of 64 additional deaths brings the total civilian death toll in U.S. air attacks to 119 since the campaign against the Islamic State began in 2014, Centcom said. The command, responsible for U.S. military operations in the Middle East, is investigating other allegations. 
 
 “Sometimes civilians bear the brunt of military action but we do all we can to minimize those occurrences, even at the cost of sometimes missing the chance to strike valid targets in real time,” Col. John Thomas, a Centcom spokesman, said in a statement. 
 
 Previously, Centcom had acknowledged only 55 deaths, the result of a lengthy investigative process that critics say has moved too slowly and has given inadequate weight to on-the-ground reports from local media, rights groups and activists. Some advocacy organizations, such as Amnesty International, have put the death toll much higher. 
 
 Centcom officials said they have been working in recent months to broaden the scope of their casualty investigations, seeking to compare information from military channels with that from external reports. Centcom has also introduced a new software program that seeks to reconcile that information and has in instances of conflicting death tolls chosen to use a higher estimate, a defense official said. 
 
 Chris Woods, director of Airwars, a Britain-based organization that tracks allegations of civilian deaths in detail, said it was a positive sign that Centcom was incorporating external reporting into its oversight in a new way. 
 
 In its report, Centcom provided details of 24 separate incidents, roughly half in Syria and half in Iraq, in each of which military officials concluded at least one civilian was inadvertently struck. They included an April 9 strike in Mosul, the militant stronghold in northern Iraq, in which Centcom concluded that one civilian entered the target area after the U.S. aircraft fired its weapon. Airwars’ examination of the incident, in contrast, said that as many as 67 people may have died. 
 
 In other incidents, the same explanation was provided for why a civilian was hit; in some cases, no explanation was offered. 
 
 Woods said the new list contained significant omissions, including a flurry of allegations that accompanied a major operation to reclaim the city of Manbij in northern Syria last summer. 
 
 One of those is a July 19 strike in the village of Tokhar, which activists said killed as many as 100 people. U.S. military officials, speaking privately, described most of those as militants but said that about 10 civilians may have died. Centcom said that incident remains under investigation. 
 
 Even as Centcom acknowledges the civilian deaths, Thomas said U.S. military officials had followed “the right processes” in each of the 24 incidents. “Significant precautions were taken, despite the unfortunate outcome,” he said. 
 
 While Centcom released redacted incident investigations early in its air campaign, it no longer does so. Officials at the command said that the documents might be obtained through Freedom of Information Act requests, even though such petitions can take years and often result in little useful information. 
 
 Woods said U.S. allies taking part in the air war against the Islamic State, which include Britain and France, must now increase their own transparency about potential civilian deaths. 
 
 Centcom’s new list of casualty incidents is below: 
 
 November 20, 2015, near Dayr Az Zawr, Syria, against an ISIL tactical unit, it is assessed that five civilians were killed and three individuals were injured after the civilians entered the target area after the aircraft released its weapon. 
 
 March 5, 2016, near Mosul, Iraq, on a strike against an ISIL weapons production facility it is assessed that 10 civilians were killed. 
 
 March 24, 2016, near Qayyarah, Iraq, during a strike against an ISIL target, it is assessed that one civilian was killed. April 1, 2016, near Raqqah, Syria, against ISIL tactical unit, it is assessed that three civilians were killed after entering the target area after the aircraft released its weapon. 
 
 April 9, 2016, near Mosul, Iraq, during a strike against an ISIL tactical unit, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 April 30, 2016, near Mosul, Iraq, against ISIL military leadership, it is assessed that five civilians were killed after entering the target area after the aircraft released its weapon. 
 
 May 25, 2016, near Mosul, Iraq, during a strike against an ISIL tactical unit, it is assessed that one civilian was killed. 
 
 May 26, 2016, near Mosul, Iraq, during a strike against ISIL fighters, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 May 29, 2016, near Mosul, Iraq, during a strike against an ISIL weapons system, it is assessed that six civilians were killed. 
 
 June 15, 2016, near Kisik, Iraq, during a strike against an ISIL weapons storage facility, it is assessed that six civilians were killed. 
 
 June 15, 2016, near Mosul, Iraq, during another strike against ISIL targets, it is assessed that two individuals were injured after entering the target area after the aircraft released its weapon. 
 
 June 21, 2016, near Ar Raqqah, Syria, during a strike targeting an ISIL headquarters building, it is assessed that three individuals were killed after entering the target area after the aircraft released its weapon. 
 
 June 23, 2016, near Ar Raqqah, Syria, during a strike against an ISIL-held building, it is assessed that four civilians were killed after entering the target area after the aircraft released its weapon. 
 
 June 26, 2016, near Mosul, Iraq, during a strike against an ISIL target, it is assessed that one individual was injured after entering the target area after the aircraft released its weapon. 
 
 June 26, 2016, near Mosul, Iraq, during another strike against an ISIL target, it is assessed that one individual was injured after entering the target area after the aircraft released its weapon. 
 
 July 3, 2016, near Manbij, Syria, during a strike against an ISIL fighting position, it is assessed that four civilians were killed. 
 
 July 10, 2016, near Manbij, Syria, during a strike against an ISIL target, it is assessed that two civilians were killed. 
 
 July 14, 2016, near Qayyarah, Iraq, during a strike on an ISIL-held building, it is assessed that one civilian was killed. 
 
 July 31, 2016, near Manbij, Syria, during a strike against ISIL fighters, it is assessed that one civilian was injured after entering the target area after the aircraft released its weapon. 
 
 August 17, 2016, near Ar Raqqah, Syria, during a strike against an ISIL target, it is assessed that two civilians were killed. August 20, 2016, near Manbij, Syria, during a strike against an ISIL artillery firing position, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon. 
 
 August 31, 2016, near Ramadi, Iraq, during a strike against an ISIL target, it is assessed that two civilians were killed. 
 
 September 7, 2016, near Dayz Az Zawr, Syria, during a strike against an ISIL oil collection point, it is assessed that one civilian was killed after entering the target area after the aircraft released its weapon.
– US Central Command says airstrikes in Iraq and Syria have killed at least 64 civilians during the past year, more than doubling the number of civilian deaths since renewed operations began in 2014, reports the Washington Post. On Wednesday, the Department of Defense released an official statement describing the review process and providing a list of deadly airstrikes. The figure of 64 is in addition to the government's previous estimate of 55, bringing the official number of civilians killed since 2014 to 119. Human rights groups say the actual figure is higher. "Sometimes civilians bear the brunt of military action,” said CentCom spokesman Col. John J. Thomas. "But we do all we can to minimize those occurrences, even at the cost of sometimes missing the chance to strike valid targets in real time." The military undertook its review of the air campaign after rights groups accused the US of a low count over the summer. As pressure built, CentCom re-examined 257 airstrikes and determined that at least 31 resulted in accidental collateral damage, reports the New York Times.