It was the first time that regime forces fired a drone near coalition forces. Further analysis was being carried out to determine the origins of the drone.
In a major escalation of tensions between Washington and troops supporting Damascus, the United States has shot down a pro-regime drone that fired towards US-led coalition forces in Syria on Thursday, a US military spokesperson said.
The armed drone "hit dirt," and there were no injuries or damage done to the coalition patrol in southern Syria.
"This clearly showed a threat even if it were a warning shot; it was something that showed a hostile intent, a hostile action and posed a threat to our forces because this drone still had munitions that were still on it," said Colonel Ryan Dillon, a spokesman for the US-led coalition fighting Daesh.
The #Coalition does not seek to fight Syrian regime or pro-regime forces. However, we remain ready to defend ourselves against any threat.— OIR Spokesman (@OIRSpox) June 8, 2017
He further added that it was the first known time that regime forces had fired at coalition forces in the area.
A US official, speaking on condition of anonymity, said the projectile landed a few hundred yards from coalition forces and failed to explode.
The official added that a US F-15 fighter jet was used to strike the drone, which was likely Iranian-made but that further analysis was being carried out.
Third strike by the US against pro-regime forces
Dillon said the US had earlier in the day carried out a strike against two pro-regime government pick-up trucks with weapons that had moved against US-backed fighters near the southern town of At Tanf.
It was the third such strike, and the second this week, by the Pentagon, which has sought to stay out of Syria's civil war to focus on Daesh in Syria and Iraq.
The concern is that such strikes could take away attention from the fight against Daesh.
SDF launches its final assault to capture Raqqa
Earlier, the Syrian Democratic Forces (SDF) launched their assault to capture Raqqa, Daesh's de facto Syrian capital.
For months, air strikes and special forces from the US-led coalition have helped them encircle Raqqa, which Daesh seized in 2014 and has used as a base to plan attacks abroad.
On Tuesday, the United States launched an air strike against Iranian-backed fighters who it said posed a threat to the US and US-backed forces in southern Syria.
A military alliance fighting in support of Bashar al Assad threatened on Wednesday to hit US positions in Syria, warning its "self-restraint" over US air strikes would end if Washington crossed "red lines."
In recent days, the US military has repeatedly warned amassing forces to stay away from a "deconfliction zone" near a garrison used by American special forces and US-backed fighters around At Tanf.
The zone was agreed with pro-regime ally Russia. Assad is also backed by Iran and Shia militias.