U.S. Central Command reported U.S. forces in the Red Sea in a “self-defense engagement” destroyed three Houthi unmanned surface vehicles Sunday.

The vehicles, which the command did not describe further, “presented an imminent threat to U.S. and coalition forces, and merchant vessels in the region,” according to a Central Command news release that day.

“This continued malign and reckless behavior by the Iranian-backed Houthis threatens regional stability and endangers the lives of mariners across the Red Sea and Gulf of Aden,” the release states.

Central Command provided no further details on the attack, including who destroyed the unmanned vehicles or how.

The Houthis have used one-way, unmanned attack boats to target shipping in the region’s sea lanes since at least January.

The U.S. Navy and other partners, including the Royal Navy, have patrolled the Red Sea and Gulf of Aden this year to counter attempts by Houthi insurgents in Yemen to interrupt commercial shipping.

The Houthi campaign was launched in sympathy with the Palestinian territory of Gaza following the Israeli army invasion of the territory, which has killed more than 24,000 people.

The Israelis began the invasion following an Oct. 7 attack on their territory by Hamas militants that killed approximately 1,200 people.