The U.S. Air Force said that it had intervened on Monday to repel an attack on the United Arab Emirates amid an escalation of tensions between the Gulf nation and the Iran-backed Houthi rebels in Yemen.

In a separate statement, the Emirati Ministry of Defense said its air defense forces had intercepted and destroyed two missiles fired by the Houthi rebels, adding that there were no casualties, although missile fragments had fallen around the capital, Abu Dhabi. It was the second Houthi attack in a week targeting the United Arab Emirates, which is part of the Saudi-led coalition that has been at war with the Houthis in Yemen for years.

“U.S. military forces successfully reacted to multiple inbound threats during an attack near Abu Dhabi,” the U.S. Air Force said, without providing further details.

At Al Dhafra Air Base in Abu Dhabi, which hosts the U.S. Air Force’s 380th Air Expeditionary Wing, American forces were on a heightened state of alert and spent about an hour in security bunkers after the missile alert sounded, according to a statement from Lt. Col. Phillip Ventura, a spokesman for the U.S. Air Forces in the Middle East.

“U.S. forces at Al Dhafra stand with the U.A.E. and our coalition partners across the region,” said Brig. Gen. Andrew Clark, commander of the 380th Air Expeditionary Wing. “We have a strong partnership with the Emiratis and will continue working together in support of our mutual interests.”

It was not immediately clear whether the U.S. and Emirati defenses were deployed in separate attacks or were responding to the same missile strike.

The Emirati defense ministry affirmed its “full readiness to deal with any threats,” and promised to take all necessary measures to protect the state from attacks, according to the state news agency WAM.

The missile fire came a week after the Houthis claimed responsibility for another attack on the Emirates targeting the airport in Abu Dhabi and a fuel depot. That attack on the fuel depot killed three people. The Saudi-led coalition struck back with airstrikes on northern Yemen, killing scores of people at a detention center and knocking out the internet across the impoverished country.

The Houthis had threatened to avenge those attacks and to attack the United Arab Emirates again.

In a video statement, a Houthi military spokesman, Yahya Sarea, said the Houthis had carried out the attack in response to an escalation by the Saudi-led coalition in Yemen and that it had also included drones and missile attacks targeting sites in Dubai, another Emirati city, and Saudi Arabia.

Mr. Sarea warned foreign companies and investors in the Emirates to leave “since it has become an unsafe country that will be targeted regularly as long as it continues its aggression and siege of the Yemeni people.”

The escalation in hostilities is fresh proof of the conflict’s obstinacy a year after President Biden took office vowing to bring the war — and one of the world’s worst humanitarian disasters — to an end.

After months of territorial gains by the Houthis, who control northern Yemen, forces backed by Saudi Arabia and the United Arab Emirates have managed to claw back some territory and shift the momentum of the war. Those offensives have snarled international efforts to push the two sides toward peace.

Mona El-Naggar reported from Cairo and Eric Schmitt from Washington, D.C. Ben Hubbard contributed reporting from Beirut, Lebanon.