At least 800 civilians have been killed by US-led coalition airstrikes against the ISIS terrorist group in Iraq and Syria since the campaign began in 2014, according to a Pentagon report released Thursday. Five more strikes, all in Syria, were investigated over the past month and found to have resulted in 15 civilian additional civilian deaths, the report stated. “We continue to hold ourselves accountable for actions that may have caused unintentional injury or death to civilians,” the coalition said in its report. However, monitoring groups say the number of civilian casualties from coalition airstrikes in the fight against ISIS is far higher than the Pentagon acknowledges. Since August 2014, more than 5,000 civilians have been killed as a result of coalition airstrikes in Iraq and Syria, according to the London-based Airwars organization that tracks civilian deaths in the anti-ISIS operations. The majority of civilian casualty allegations are currently from coalition airstrikes in Syria. The Pentagon says they are still assessing 695 reports of civilian casualties, more than 400 of which are from strikes carried out in Syria. US-backed Syrian forces retook the city of Raqqa from ISIS control in October and pushed ISIS militants out of a swath of territory along the Euphrates river valley in the following weeks. Each investigation that found an allegation credible determined it was "more likely than not" that a coalition strike resulted in a civilian casualty, the report stated. "Although all feasible precautions were taken and the decision to strike complied with the law of armed conflict, unintended civilian casualties unfortunately occurred," the Pentagon added. Since the start of the campaign against ISIS, the coalition has carried out more than 28,000 strikes and has received 1,790 reports of potential civilian casualties, the report said. These airstrikes have contributed to fueling progress against ISIS by Iraqi and Syrian ground forces, reducing ISIS-held territory to pockets of desert along the Iraqi-Syrian border.