President Joe Biden ordered the U.S. military to carry out retaliatory airstrikes against Iranian-backed militia groups after three U.S. servicemembers were injured in a drone attack in northern Iraq, Paralel.Az reports citing Associated Press.

National Security Council spokeswoman Adrienne Watson said one of the U.S. troops suffered critical injuries in the attack that occurred earlier Monday. The Iranian-backed militia Kataib Hezbollah and affiliated groups, under an umbrella of Iranian-backed militants, claimed credit for the attack that utilized a one-way attack drone.

Biden, who is spending Christmas at the presidential retreat at Camp David, Maryland, was alerted about the attack by White House national security adviser Jake Sullivan shortly after it occurred on Monday and ordered the Pentagon and his top national security aides to prepare response options to the attack on an air base used by American troops in Erbil.

Sullivan consulted with Defense Secretary Lloyd Austin. Biden’s deputy national security adviser, Jon Finer, was with the president at Camp David and convened top aides to review options, according to a U.S. official, who was not authorized to comment publicly and requested anonymity. Within hours, Biden convened his national security team for a call in which Austin and Gen. CQ Brown, the chairman of the Joint Chiefs of Staff, briefed Biden on the response options. Biden opted to target three locations used by Kataib Hezbollah and affiliated groups, the official said.

The U.S. strikes were carried out at about 4:45 a.m. on Tuesday in Iraq, less than 13 hours after the U.S. personnel were attacked. According to U.S. Central Command, the retaliatory strikes on the three sites, “destroyed the targeted facilities and likely killed a number of Kataib Hezbollah militants.”

“The President places no higher priority than the protection of American personnel serving in harm’s way,” Watson said. “The United States will act at a time and in a manner of our choosing should these attacks continue.”