Washington — Three American service members were killed and 25 more were injured in an unmanned aerial drone attack on a base in Jordan on Sunday, President Biden and the U.S. military said.

In a statement, the president blamed the attack on “radical Iran-backed militant groups operating in Syria and Iraq.” Mr. Biden said the attack happened at a base in northeast Jordan, close to the border with Syria.

U.S. Central Command, which oversees forces in the Middle East, put the number of wounded at 25, and said the identities of those killed would be withheld for 24 hours after their families had been notified. A U.S. official said the attack occurred at an outpost in eastern Jordan known as Tower 22.

The attack comes as tensions between the U.S. and Iran’s proxies in the region have soared to new levels in recent weeks. Yemen’s Iranian-backed Houthi rebels began attacking shipping vessels in the Red Sea in October to protest Israel’s war with Hamas in Gaza. The U.S. and its allies began conducting airstrikes against the group in Yemen earlier this month. 

On Friday, the militants launched a missile at the USS Carney, the first time the Houthis had targeted a U.S. warship. The destroyer shot the missile down without any injuries. 

The week before, the U.S. military said two Navy SEALs were lost at sea when they went overboard while attempting to board an Iranian vessel that was delivering “advanced conventional weapons” to the Houthi rebels.

In his statement, Mr. Biden called Sunday’s attack in Jordan “despicable and wholly unjust,” noting that “we will hold all those responsible to account at a time and in a manner our choosing.” The White House said top aides briefed the president about the attack on Sunday Morning, and a U.S. official said a meeting is expected at the White House later in the day regarding a response.

Congressional Republicans reacted angrily to news of the attack, calling on the Biden administration to retaliate against Iran. House Speaker Mike Johnson said the administration “must send a crystal clear message across the globe that attacks on our troops will not be tolerated.” Sen. Lindsey Graham of South Carolina, a prominent GOP defense hawk, said the U.S. should strike “targets of significance” inside Iran itself to deter future attacks.

“Hit Iran now,” Graham said. “Hit them hard.”

Margaret Brennan contributed reporting.