U.S. and allied strikes against the Islamic State may have killed as many as 6,000 civilians in 2017. Airwars, which investigates allegations of civilian casualties by using social media and other information sources, said that between 3,923 and 6,102 noncombatants were "likely killed" in air and artillery strikes by the United States and its partners in 2017. The estimate for Iraq and Syria was more than triple that of the year before. While the Airwars data includes strikes by the United States and partner nations including Britain and France, most of the military activity has been conducted by American forces. The group's estimate is vastly higher than the figure put forward by U.S. Central Command, which conducts its own investigations of selected U.S. strikes. According to its most recent public report, Centcom has determined that at least 817 civilians have been killed since the air campaign began in 2014.