WASHINGTON — American warplanes in southern Syria attacked a convoy of pro-government forces on Thursday after they ignored warnings and violated a restricted zone around a base where American and British Special Forces are training Syrian militia fighters, Pentagon officials said.
The American action appeared to be the third time in recent months that the United States military had attacked forces loyal to President Bashar al-Assad of Syria.
In the most serious of two encounters on Thursday, more than 20 vehicles — including a T-72 tank and a bulldozer — drove within 18 miles of the al-Tanf base in southern Syria housing the American and British Special Forces, breaching the so-called deconfliction zone radius around the encampment.
Low-flying American aircraft buzzed the convoy and fired a warning strike, trying to get the vehicles to reverse course, the Pentagon officials said, but when the convoy continued, the planes opened fire.
In a second incident, a Syrian SU-22 fighter-bomber that entered the deconfliction zone was intercepted by a pair of F-22 fighter aircraft, but it was not fired upon and left the area, the officials said.