WASHINGTON — The main air defense system at a coalition military base in northeast Syria was “not fully operational” when a suspected Iranian drone hit the installation Thursday, killing a U.S. contractor and injuring six other Americans, two U.S. officials said Friday.
It was unclear why the system was not fully operational and what difference that made in defending the base. The circumstances are under investigation, military officials said.
It was also unclear whether the attackers had detected that vulnerability or just happened to send the drone at that time, officials said. They asked for anonymity to discuss an ongoing investigation.
The drone strike happened at a moment when U.S. forces in northeast Syria are on high alert against attacks from Iran-backed militias; there have been 78 such attacks since January 2021, a top American general said Thursday. But the Avenger missile defense system at the base, called RLZ, may have been experiencing an unexpected maintenance problem at the time of the attack, one of the officials said.
The base near Hasakah, Syria, has other defenses against air and other attacks, but even all these systems combined are not foolproof.
After U.S. intelligence analysts concluded that the drone was of “Iranian origin,” the United States retaliated by launching air-strikes against militant sites linked to Iran’s Revolutionary Guard, the Pentagon said. The F-15E fighter jets attacked a munition warehouse, a control building and an intelligence-collection site in eastern Syria, two senior U.S. military officials said.
“As President Joe Biden has made clear, we will take all necessary measures to defend our people and will always respond at a time and place of our choosing,” Defense Secretary Lloyd Austin said Thursday. “No group will strike our troops with impunity.” The U.S. airstrikes killed eight pro-Iran fighters, according to the Syrian Observatory for Human Rights, a group in Britain that tracks the conflict.
U.S. military officials said that Iran-backed militias on Friday fired about 10 rockets at a second U.S. base in the area, called Green Village, in response to the airstrikes. The officials said there were no U.S. casualties from those attacks.
The attacks are likely to stoke tensions with Iran, which Biden administration officials call the largest security threat in the Middle East.