The attack coincided with the arrival of trucks with military equipment at the base, according to the broadcaster. US soldiers reportedly responded with shelling and stun grenades.
US Defence Secretary Mark Esper said earlier in the week that US troops in northeastern Syria had finished re-manoeuvring as needed and that the total number of troops on the ground would remain at around 600.
The movement of US forces has been causing much uncertainty in Syria since US President Donald Trump abruptly announced a withdrawal of troops in early October. The pullout was never complete, however, with the troops eventually setting up a camp at Syrian oil fields controlled by allied Kurds, claiming to ensure that resources were not taken by Daesh*.
Trump, while at the NATO Summit this week, credited US forces with protecting the oil from falling back into the hands of terrorists.
*Daesh [ISIS, ISIL, Islamic State] - a terrorist group banned in Russia and a number of other countries