The coalition said troops at Green Village in Deir ez-Zor governorate received two rounds of indirect fire. Two members of the coalition were injured and the rounds caused two fires to break out.

Both service members were able to return to duty following treatment and the fires were quickly managed, according to the coalition.

Sources from the Syrian Observatory for Human Rights (SOHR) reported the sound of explosions before noon in the area of the base, but at the time were unaware if the sound came from military drills or a rocket attack.

The SOHR said the reports came hours after similar news of rockets fired from areas across the Euphrates held by forces that truck the al-Omar oil field where Green Village base is located.

The US-led Special Operations Joint Task Force-Levant (SOJTF-L) said one soldier was treated and released while another remained under evaluation for a possible traumatic brain injury. SOJTF’s initial tweet was later deleted, and replaced with the coalition’s statement.

The barrage is the first of its kind reported against US forces in Syria since January, when the coalition retaliated against militia for a previous rocket attack near the same base. No American personnel were reported hurt in that incident.

Last October, US Special Forces evacuated parts of the al-Tanf garrison on Syria’s southern border with Iraq and Jordan after receiving intelligence of an impending drone barrage by some militias.

The isolated outpost sustained damage to a gym and sleeping quarters, but no coalition personnel were hurt in the attack.

Then-top commander of US forces in the Middle East, Gen. Kenneth “Frank” McKenzie, later said the barrage was designed to kill. He credited quick thinking by lower-level commanders for averting casualties.

Thursday’s attack is the latest indication that network of proxy militias will continue to harass US troops in the region.

The Pentagon’s top policy official for the Middle East, Dana Stroul, said on Tuesday that US forces in northeast Syria “experience on a very regular basis threats from Iran and Iran-backed proxies.”

There have been roughly 2,500 US troops in Iraq and some 900 in Syria in the wake of the multinational war effort against the Islamic State group. Stroul emphasized that US troops would remain in those countries and in the wider region, even as Washington focuses on competition with China.

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