WATCH: U.S. forces in eastern Syria conduct self-defense strike, Pentagon says

WASHINGTON — U.S. forces conducted a self-defense strike Tuesday in the vicinity of Mission Support Site Euphrates, a U.S. base in eastern Syria, against three truck-mounted multiple rocket launchers, a T-64 tank and mortars that Pentagon press secretary Maj. Gen. Pat Ryder said presented “a clear and imminent threat” to U.S. troops.

Watch Ryder speak in the player above.

The self-defense strike occurred after rockets and mortars were fired that landed in the vicinity of the base, Ryder said. The Pentagon is still assessing who was responsible for the attacks — that there are both Iranian-backed militias and Syrian military forces that operate in the area.

Ryder said the attack was not connected to the offensive that is ongoing in Aleppo, where Syrian jihadi-led rebels taken over the country’s largest city. The U.S. has about 900 troops in Syria to conduct missions to counter the Islamic Stage group.