US-backed Syria fighters kill 20-plus IS fighters

WASHINGTON (AP) - An American-supported Syrian opposition force killed more than 20 Islamic State fighters in an area near the Jordanian and Iraqi borders, U.S. officials said. The clash was described as a response to the Syrian army's failure to prevent IS from moving freely through its lines.

"Despite the presence of Russian-backed, pro-Syrian regime forces in the area, Daesh still finds ways to move freely through regime lines and pose a threat," U.S. Brig. Gen. Jonathan Braga said, using an alternative name for the Islamic State.

Braga, the director of operations for the U.S.-led coalition that is fighting IS in Syria and Iraq, said the IS fighters had slipped through Syrian lines in the tri-border area near at-Tanf on Wednesday. They were confronted by a U.S.-backed Syrian opposition force known as the Maghawir al-Thawra. In a pre-dawn firefight, more than 20 IS fighters were killed and a number were captured.

Another U.S. official, who spoke on condition of anonymity because he was not authorized to publicly provide details, said about 15 IS fighters were detained by the U.S.-backed group.

The Syrian government has fought against IS, but Braga said this is the second time in recent weeks that IS fighters fleeing a contested area further north in the Mid-Euphrates River Valley have moved freely through Syrian-controlled territory.

Separately, the Pentagon said two Russian Su-25 fighters flew through an unofficial line separating Russian and American air forces in eastern Syria along the Euphrates River on Wednesday. U.S. Air Force F-22 combat jets operating in the area launched warning flares. The incident was the latest in a series of Russian air activities viewed by the U.S. as potentially risking a confrontation or accident in the Euphrates River area as battles against IS fighters continue.