A misdirected airstrike by the U.S.-led coalition earlier this week killed 18 allied fighters battling the Islamic State of Iraq and the Levant group (Isil) in northern Syria, the U.S. military said on Thursday.
The American Central Command said coalition aircraft were given the wrong co-ordinates by their partner forces, the predominantly-Kurdish Syrian Democratic Forces (SDF), for the strike on Tuesday that was intended to target IS militants south of their Tabqa stronghold, near the extremists' de facto capital, Raqqa. The strike hit an SDF position instead.
Several nations have lent their air power to the U.S.-led coalition to defeat the Islamist group, and it wasn't clear which air force was behind the errant strike.
The SDF acknowledged the strike, saying a number of its fighters were killed and wounded. On Thursday, the group held funerals for 17 of its fighters in the border town of Tal al-Abyad, the SDF-linked Hawar news agency said, though it did not say whether they were killed in the friendly fire incident.
An activist-run group, Raqqa is Being Slaughtered Silently, said three days of mourning had been declared for the town. The Britain-based Syrian Observatory for Human Rights said 25 SDF fighters were killed in the last two days of battle.
The SDF, meanwhile, announced the launch of a new phase of its campaign to retake Raqqa. The Kurdish fighters, with U.S.-led air and ground support, have surrounded Tabqa, some 40 kilometers (25 miles) southwest of the city and are working to clear Islamic State militants out of Jalab Valley, north of Raqqa.
The SDF says it wants to isolate Raqqa before attacking it. Its closest position is less than eight kilometers (five miles) northeast of the city. But the countryside south of Raqqa is still under IS control.