A review of past air and artillery strikes has found that another 119 civilians were killed by the US-led coalition in Iraq and Syria, pushing the total number of such deaths to 603. In a statement Friday, the coalition said that in May it completed an analysis of 141 reports of civilian deaths dating back to when operations to defeat the Islamic State group got underway in late 2014. "To date, based on information available, (the coalition) assesses that, it is more likely than not, at least 603 civilians have been unintentionally killed by coalition strikes" since the anti-IS campaign began, the statement read. Aside from probing civilian death reports that came in from coalition pilots and through social media and other channels, military investigators also began wading their way through a huge backlog of hundreds of allegations reported by the website Airwars.org. The London-based collective of journalists and researchers has always had civilian death tolls that are wildly divergent from those acknowledged by the coalition. According to the most recent Airwars tally, 4,354 civilians have been killed in coalition strikes. Major Michael Burns, who compiled the coalition statement, told AFP that of the 80 Airwars reports it looked at in May, 10 were "credible" and 70 were "non-credible." Among all the reports the coalition examined in May was an April 17 strike on an IS headquarters building that caused secondary explosions, killing 25 civilians in adjacent structures and wounded 40 more. And on January 21, near Mosul in Iraq, a strike on a suicide car bomb caused secondary explosions that killed 15 civilians. Observers say the US-led coalition has been taking greater risks with civilian lives since President Donald Trump took office and gave the military greater leeway in how it conducts strikes, but officials insist the rules of engagement are unchanged. "Although all feasible precautions were taken and the decision to strike complied with the law of armed conflict, unintended civilian casualties unfortunately occurred," the statement read.