The United States responded to an attack that killed two US soldiers with airstrikes against numerous targets in Iraq on Thursday.
Fox News' Jennifer Griffin reported that military sources told her the airstrikes were concentrated on Iranian-backed Shia militias.
The attack on coalition forces at Camp Taji on Wednesday was suspected to be coordinated by Iranian-backed militias. In addition to the U.S. fatalities, a British service member was also killed in the attack by as many as 30 rockets. The attack also injured another dozen service members.
Iran had previously launched attacks against U.S. forces in January as retaliation for the drone strike that killed Iranian military leader Qassem Soleimani near the Baghdad airport. While no service members were killed in that attack, more than a hundred troops suffered traumatic brain injuries.
The newest attack on U.S. forces on Wednesday coincided with what would have been Soleimani's 63rd birthday.
Earlier on Thursday, Defense Secretary Mark Esper foreshadowed the retaliation from the United States.
"I have spoken with the president," said Esper. "He's given me the authority to do what we needed to do."
The retaliatory attack is designed to be a "proportional" response in order to deter future attacks, according to the Pentagon.