U.S. warplanes struck a convoy of pro-Syrian forces after they violated a restriction zone in the southern part of the country. The convoy drove near an airbase which houses U.S. forces and allies.

Government officials say this happened despite “Russian attempts to dissuade” the convoy and warning shots being fired. Reuters reports the convoy consisted of dozens of vehicles, including a tank and construction vehicles.

Reuters also reporting a U.S. official, who wanted to remain anonymous, said the group might have been trying to establish a position near a garrison used by U.S. and partner forces.