U.S. officials say an American airstrike has hit pro-Syrian government forces in southern Syria as they were setting up fighting positions in a protected area.

The officials say the strike near Tanf hit a tank and a bulldozer and forces there, but it was not clear if they were Syrian army troops or other pro-government allies.

One official says the pro-regime forces loyal to Syrian President Bashar al-Assad had entered a so-called “de-confliction” zone without authorization and were perceived as a threat to U.S.-allied troops there.

The officials say the strike was a defensive move to protect the U.S. allies. It wasn’t clear if U.S. forces were there.


Syrian municipality workers remove rubble from a main street at the mountain resort town of Zabadani in the Damascus countryside Thursday. The airstrike was an apparent signal to President Bashar al-Assad to keep his forces out of a zone where U.S.-backed rebels are fighting the Islamic State group. (Hassan Ammar/Associated Press)

The officials weren’t authorized to speak publicly on the matter and demanded anonymity.

Convoy hit

Several Syrian opposition media groups with activists in the area say the airstrike hit a convoy of government troops and allied militiamen on the road to the Tanf area, where Syria’s borders with Jordan and Iraq meet.

One opposition media group, the Palmyra News Network, says the attack at the Zarka juncture, about 27 kilometres from the border, destroyed a number of vehicles and led to casualties.

The area has been a source of tensions as both government forces and U.S.-backed rebels advance there. Both the government forces and the rebels are trying to force ISIS militants from the area.

The Revolutionary commandos, or Maghaweer al-Thawra, a U.S.-backed group, shared a report about the airstrike on their Twitter account.

The airstrikes comes on the same day that UN-mediated talks got underway with a Syrian government delegation.

The head of the delegation said his team led the drive to start “informal meetings” on a constitutional process.

Bashar al-Ja’afari, who is also Syria’s UN ambassador, says the subject was brought up on the government’s “own initiative,” but insisted that Damascus “will not accept any interference” on the constitution.

Thursday’s announcement of the talks-within-talks among constitutional experts appear to be the only development so far in the sixth round of largely unproductive discussions that have been hosted by UN envoy Staffan de Mistura since early 2016.​