US Army bases stationed near the Conoco gas field in the Deir al-Zor region of eastern Syria were targeted by mortar shells and missiles on Thursday, according to Syria's state-owned SANA news agency.
Explosions were heard inside the American base, local sources reportedly told SANA, which reported that the American military quickly moved to close the area surrounding the base.
No casualties were reported in the attack.
Latest fighting in Syria between US, pro-Iran groups
The strikes came in response to two rounds of airstrikes conducted by the US on sites in the Deir al-Zor region linked to the Islamic Revolutionary Guards Corps (IRGC) and Iran-affiliated groups operating in Syria and Iraq.
The US airstrikes targeted Iran-backed militias in the city of Al-Mayadin and Saker Island, which were in response to an attack by pro-Iran militants where one American was lightly injured, CENTCOM stated. The soldier has since been treated and returned to duty.
In a statement released on Thursday, the command said four enemy fighters were killed and seven rocket launchers were destroyed in the retaliatory strikes. The American forces used AH-64 Apache attack helicopters, AC-130 gunships and M777 artillery, it said.
US 'monitoring' Syria situation amid nuke deal revival
CENTCOM head Gen. Michael Kurilla said on Wednesday that the US is "closely monitoring the situation."
"We have a total spectrum of capability to mitigate threats across the region, and we have every confidence in our ability to protect our troops and coalition partners from attacks," he said.
"We have a total spectrum of capability to mitigate threats across the region"
CENTCOM head Gen. Michael Kurilla
This latest round of fighting comes as negotiations for the revival of the 2015 Iran nuclear deal between the Islamic Republic and world powers are set to reach their 10th round of talks.