The U.S. military on Sunday conducted airstrikes on facilities used by Iran-backed militia groups in the Iraq-Syria border region. 

The targets are facilities Iran-backed militias have used in unmanned aerial vehicle or drone attacks against U.S. personnel and facilities in Iraq, according to a statement from Pentagon spokesperson John Kirby. 

“Given the ongoing series of attacks by Iran-backed groups targeting U.S. interests in Iraq, the President directed further military action to disrupt and deter such attacks,” Kirby said in the statement. 

A defense official told CBS News that all the targets — command and control and logistics for drones —  were hit. There were no indications of civilian casualties. 

According to Kirby’s statement, the U.S. strikes targeted operational and weapons storage facilities at two locations in Syria and one location in Iraq.

A U.S. official said the locations that were hit included the site from which the drones took off, recovered and were controlled. The official also said there have been “at least five” drone attacks by Iranian-backed militias against bases in Iraq where U.S. troops, contractors or other personnel are located. 

The strike was carried out by U.S. F-15s and F-16s.  

This is the second strike against Iranian backed militias during the Biden administration.  In February, two F-15 Eagles dropped seven 500-pound bombs, completely destroying nine buildings and damaging two. That was  retaliation for a strike that killed an American contractor.  

No Americans have been killed since then, although one American died of a heart attack during a rocket attack.

A second defense official said no Americans have been killed by drone strikes in Iraq, but the Iranian-backed militias were “using them in an increasingly aggressive way.” One drone strike hit a hangar used by the CIA in Erbil.