A US base at the Al-Omar oil field in Syria's northeast was targeted with a missile attack on Friday morning, according to Lebanese pro-Iranian TV channel Al Mayadeen and a security source.
The source told Reuters the attack took place at around 11 a.m. local time and it was unclear whether it had caused casualties.
There was no immediate US comment on the reported attack.
Attack on US base follows American airstrikes in Syria
It followed US airstrikes in Syria early Friday morning against Iran-aligned groups that the Pentagon blamed for a drone attack on Thursday that killed an American contractor, wounded another and also hurt five US troops.
Thursday's attack took place at a coalition base near Hasakah in northeast Syria, the Pentagon said in a statement.
The US intelligence community assessed that the one-way attack drone was Iranian in origin, the Pentagon said, a conclusion that could further aggravate already strained relations between Washington and Tehran.
US troops have come under attack by Iranian-backed groups about 78 times since the beginning of 2021, according to Army General Erik Kurilla, who oversees US troops in the Middle East as the head of Central Command.
Fatalities are extremely rare.