Air Force B-2 bombers struck five underground weapons facilities in what may be a signal from the Biden administration to Iran.

The bombing is designed to stop the Iran-backed group from attacking commercial and military vessels in the Red Sea and the Gulf of Aden, the Pentagon said.

It was the first time the U.S. used these stealth bombers against the Houthis, who have targeted commercial and military vessels in the Red Sea and Gulf of Aden.

While it wasn't immediately clear how much damage the strikes caused, the attack appeared to be the first use of the B-2 in combat in years.

The US says it has carried out "precision strikes" against five weapons storage locations in areas of Yemen controlled by the Houthi movement. Defence Secretary Lloyd Austin said B-2 Spirit stealth bombers were part of the operation that targeted hardened underground facilities housing missiles and other munitions that the Iran-backed group had used to attack civilian and military ships.

The Pentagon said the U.S. launched airstrikes against Houthi targets in Yemen with B-2 stealth bombers. The strikes targeted five underground weapons facilities. NBC News' Meagan Fitzgerald reports on the first time that the U.