The U.S. led-coalition in Syria struck several launch sites for short-range rockets believed to be intended for attacks on an installation used by U.S. troops in eastern Syria, officials said Tuesday.

The strikes against the launch sites apparently were conducted by U.S. forces, but a statement issued by the coalition did not specify who carried them out. The statement offered few details beyond saying the sites “posed an imminent threat in the vicinity of Green Village, Syria,” and were struck in self defense.

Green Village, just east of the Euphrates River, is an installation used by some of the several hundred U.S. forces in Syria.

Pentagon spokesman John Kirby said airstrikes were not used against the launch sites. He did not elaborate.

“One of the reasons these sites were hit was we had reason to believe that they were going to be used as launch sites for attacks on Green Village,” Kirby said. “So clearly our men and women remain in harm’s way and we have to take that threat very seriously and we always have the right of self defense.”

Kirby said he could not comment on which group may have intended to use the rocket sites. The pre-emptive attack on the sites followed two separate incidents this week in Iraq in which explosives-laden drones were shot down before they could attack an Iraqi military base housing U.S. troops in western Iraq and a facility housing U.S. advisers at Baghdad airport.

Commenting on those drone incidents in Iraq on Monday and Tuesday, Kirby said the United States has not conclusively determined who was behind them, but he added, “these kinds of attacks are very much in keeping with the kind of attacks we’ve seen from Iran-backed militias in Iraq and in Syria, and so obviously our working-level assumption is that such groups were responsible for these.”

A January 2020 U.S. drone strike at Baghdad’s airport killed Gen. Qassim Soleimani, who was the head of Iran’s elite Quds Force, and Abu Mahdi al-Muhandis, deputy commander of Iran-backed militias in Iraq.

Pro-Iran Shiite factions in Iraq have vowed revenge for the killings.

The United States has about 2,500 troops in Iraq acting as trainers and advisers to Iraqi security forces.

(AP)