The U.S. military said late on Saturday that unidentified forces fired a rocket at a compound in Syria hosting U.S. troops and partnered local forces, but failed to cause any injuries or damage.
The military, in a short statement, said the 107 mm rocket failed to impact anything inside the Rumalyn Landing Zone U.S. compound in northeast Syria.
"Additional rockets were found at the launch site," said the U.S. military's Central Command, which oversees U.S. troops in the Middle East.
Central Command did not say who it believed might be responsible for the failed attack.
It came just two days after a rare U.S. helicopter raid on a government-held village in Syria's northeast killed an Islamic State militant on Thursday, followed hours later by a separate U.S. air strike later that killed two other militants.