Beirut, 5 Feb

A drone attack on a base housing US troops in eastern Syria killed six allied Kurdish fighters late on Sunday, in the first significant attack in Syria or Iraq since the US launched retaliatory strikes over the weekend against Iran-backed militias that have been targeting its forces in the region.

The U.S.-backed, Kurdish-led Syrian Democratic Forces said on Monday the attack hit a training ground at al-Omar base in Syria's eastern province of Deir el-Zour and accused “Syrian regime-backed mercenaries” of carrying out the attack. No casualties were reported among U.S. troops.

An umbrella group of Iran-backed Iraqi militias, dubbed the Islamic Resistance in Iraq, released a video claiming responsibility for the attack and showing them launching a drone from an unspecified location.

In late January, a drone attack by the same group killed three U.S. troops and wounded dozens more at a desert base in Jordan. The U.S. military launched dozens of retaliatory strikes targeting Iran-backed militant groups in western Iraq and eastern Syria and also struck the Houthis in Yemen.

The umbrella group has launched dozens of drone attacks on U.S. military bases and troops in Iraq and Syria, and has called for the withdrawal of American soldiers from both countries.

The attack comes as tensions flare across the Middle East amid the Israel-Hamas war, which was sparked by Hamas' rampage in southern Israel on Oct. 7.

Meanwhile, Britain-based opposition war monitor Syrian Observatory for Human Rights said at least seven SDF fighters were killed in the attack on Sunday and at least 18 others wounded, some in critical condition. It did not say whether any U.S. military personnel were among the casualties.

The attack late Sunday came two days after the U.S. military carried out strikes against militant targets linked to Iran in Syria and Iraq.

The SDF said it has the right to respond to the attack.

The U.S. military said it struck four anti-ship missiles on Sunday that were prepared to be fired at vessels in the Red Sea from Houthi rebel-controlled areas in Yemen.

In a statement early Monday, the U.S. Central Command said the strikes were in self-defense and came after forces determined the missiles “presented an imminent threat to U.S. Navy ships and merchant vessels in the region.”

Sunday's strikes came a day after the U.S. and Britain launched a second wave of strikes against the Houthis, meant to degrade the Iranian-backed group' capabilities to attack vessels in the Red Sea. The U.S. and Britain said they hit 36 Houthi targets.