The U.S. launched airstrikes against Iranian forces and militias in Syria and Iraq as retaliation for the drone attack that killed three American soldiers, pulling the administration of U.S. President Joe Biden even deeper into the conflict that erupted when Hamas militants struck Israel in October.

Aircraft including long-range B-1 bombers flown from the U.S. struck 85 targets at seven locations linked to Iran’s Islamic Revolutionary Guards Corps’ Quds Force and to militant groups Iran funds, according to U.S. officials. Targets included command-and-control facilities and supply depots for rockets, missiles and drones, U.S. Central Command said.

The airstrikes had been seen as all but inevitable after the Jan. 28 attack on a U.S. base in Jordan, in which three soldiers were killed and many more were wounded. Biden had sought to calibrate the U.S. response to send a message to Iran and degrade the militant groups’ ability to attack American forces while avoiding a bigger conflict.