Mistaken coalition airstrike in Syria kills 18 U.S.-backed local forces

An airstrike by the U.S.-led coalition in Syria mistakenly killed 18 soldiers from a U.S.-backed rebel force battling the Islamic State, the military said Thursday.

The latest incident was the fourth time since early March that American-led airstrikes may have killed noncombatants.

The coalition airstrike occurred Tuesday near Tabqah, where U.S.-backed Syrian Democratic Forces are engaged in a key battle against the Islamic State over a strategically important dam. Those troops are the main U.S.-backed force battling the Islamic State in Syria.

“The strike was requested by the partnered forces, who had identified the target location as an ISIS fighting position,” U.S. Central Command said in a statement, using an acronym for the Islamic State. "The target location was actually a forward Syrian Democratic Forces fighting position."

Civilian and allied deaths resulting from anti-ISIS bombing campaigns are on the rise. According to some estimates, up to 200 people died during a March 17 airstrike in Mosul, Iraq's second largest city. It was potentially the largest single loss of innocent lives to U.S.-led coalition strikes since the fight against the Islamic State began in 2014. The U.S. is investigating.

A U.S. airstrike in a rural area of Raqqa province killed more than 20 noncombatants in a school last month. Earlier in March, the Syrian Observatory for Human Rights also said 42 people, most of whom were civilians, died in a U.S. bombing in the town of Al Jinah.

Airwars.org, a non-profit organization, says alleged civilian deaths from coalition airstrikes in Iraq and Syria rose from 585 in the last quarter of 2016 to 2,580 in the first quarter of 2017. The group acknowledges, however, that many of the reports are unconfirmed.

The U.S. military is supporting Syrian Democratic Forces with airstrikes, helicopter gunships and Marine artillery in the battle around Tabqah, which is part of an overall offensive to isolate and then clear Raqqa of the militants.

“The coalition is in close contact with our SDF partners who have expressed a strong desire to remain focused on the fight against ISIS despite this tragic incident,” the statement said. “The coalition is assessing the cause of the incident and will implement appropriate safeguards to prevent similar incidents in the future.”