Hodeida, Yemen — Yemen's Iran-backed Houthis on Friday threatened to escalate attacks on Red Sea shipping after overnight strikes by the United States and Britain that the rebels said killed 16 people.

Three officials told CBS News national security correspondent David Martin on Friday that the U.S. used a 5,000-pound bunker-buster bomb as part of the joint strike against Houthi targets. The GBU-72 bomb was dropped by a U.S. Air Force jet in an effort to destroy an underground Houthi facility. One official said the bomb hit the target, but it wasn't yet clear if it had been destroyed or if there were any civilian casualties.

The Houthis, who control much of Yemen, said 16 people were killed and 40 more wounded, including an unspecified number of civilians, but there was no independent confirmation of those numbers. If confirmed, it would be one of the deadliest strikes since the U.S. and the U.K. started their campaign in January against the Houthis, whose rocket attacks have severely disrupted the vital Red Sea trade route.

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The Iran-backed Houthis have carried out scores of drone and missile attacks on vessels in the Red Sea and Gulf of Aden, including U.S. warships, since November, citing solidarity with Palestinians in the Gaza Strip over the Israel-Hamas war.

The U.S. Central Command, CENTCOM, said 13 Houthi sites were targeted in the latest strikes.

"The American-British aggression will not prevent us from continuing our military operations," Houthi official Mohammed al-Bukhaiti said on X, formerly Twitter, vowing to "meet escalation with escalation."

In response, the rebels launched a missile attack on the U.S. aircraft carrier USS Dwight D. Eisenhower in the Red Sea, according to Houthi spokesman Yahya Saree, who added that the group "will not hesitate to respond directly and immediately to every new aggression on Yemeni territories."

U.S. military officials did not immediately comment on the Houthi claim to have targeted the USS Eisenhower.

Yemen's Houthi-controlled Al-Masirah TV network broadcast a video showing bloodied men wounded in a purported strike on a building housing a radio station in the western port city of Hodeida. The channel showed victims receiving treatment at a hospital, although the authenticity of the images could not be independently verified.

A hospital employee in Hodeida said many militants were among those killed and wounded in the attack but was unable to give exact figures.

The British defense ministry said its warplanes launched strikes in "a joint operation with U.S. forces against Houthi military facilities."

The ministry said intelligence indicated two sites near Hodeida were involved in the attacks on shipping, "with a number of buildings identified as housing drone ground control facilities and providing storage for very long-range drones, as well as surface-to-air weapons."

Another "command and control" site had been identified further south, it said in a statement.

British Prime Minister Rishi Sunak said "the strikes were taken in self-defense against an ongoing threat," adding the rebels had carried out 197 attacks since November.

CENTCOM said the strikes were "necessary to protect our forces, ensure freedom of navigation, and make international waters safer and more secure."

Iran condemned the U.S.-U.K. military action, saying it aims to "spread insecurity in the region."

The "governments of the United States and the United Kingdom are responsible for the consequences of these crimes against the Yemeni people," said its foreign ministry spokesman, Nasser Kanani.

Since January, the United States and Britain have launched repeated strikes on Houthi targets in Yemen in response to the rebels' harassment of shipping. In February, the Houthis held a mass funeral in Sanaa for 17 fighters they said were killed in U.S. and British strikes.

The U.S. and British strikes have not stamped out the campaign by the rebels, who have vowed to target American and British vessels as well as all ships heading to Israeli ports.

The Houthis also said they had shot down a U.S. MQ-9 Reaper drone with a surface-to-air missile, claiming it was the sixth such aircraft they have downed in recent months.

In:
• War
• Iran
• Red Sea
• Houthi Movement
• Hamas
• Israel
• U.S. Navy
• U.S. Air Force
• Yemen
• Gaza Strip
• Missile Launch