Five drones on Friday targeted a US base in the Al-Tanf region in southern Syria, a local source said.
Four of the drones were shot down by US-led coalition forces while the remaining hit the base, the source said on condition of anonymity due to restrictions on speaking to the media.
No casualties were reported in the attack.
The identity of the drones and the point from which they took off could not immediately be determined.
Al-Tanf is located at the border triangle between Syria, Jordan and Iraq.
US military bases in Syria have been attacked by drones and missiles launched from areas controlled by Iran-backed groups.
