Yemen’s Iran-backed Houthi rebels claimed on Monday to have twice attacked an American aircraft carrier group within 24 hours, calling it retaliation for deadly US strikes.

The Houthis initially said they launched 18 missiles and a drone at the “aircraft carrier USS Harry Truman and its accompanying warships” in the Red Sea, before hours later claiming to have fired a second round.

There was no immediate comment from the United States about the Houthis’ claimed attacks.

In a statement posted to Telegram on Monday, a Houthi spokesperson said the attacks on the carrier group were “in retaliation to the continued American aggression against our country.”

Washington has vowed to keep striking Yemen until the rebels stop attacking Red Sea shipping, with President Donald Trump warning he will use “overwhelming lethal force.”

The Houthi health ministry said women and children were among the 53 people killed and 98 wounded in US strikes on Saturday.

Houthi media reported more explosions on Sunday night, accusing the Americans of targeting a cotton ginning factory in the western region of Hodeida as well as the Galaxy Leader, an Israeli ship captured more than a year ago.

Houthi leader Abdulmalik al-Huthi called on Yemenis to march on Monday in defiance.

In response to the latest escalation along the maritime trade route, the United Nations has urged both sides to “cease all military activity.”

The Iran-backed Houthis, who control much of the Arabian Peninsula’s poorest country, have attacked Israel and Red Sea shipping throughout the Gaza war, claiming to be acting in solidarity with Palestinians.

Before this weekend’s targeting of the US carrier group, the Houthis had not claimed attacks in the Red Sea and Gulf of Aden since 19 January, when a ceasefire began in the Gaza Strip.

The group said it relaunched its attacks over Israel’s halting of humanitarian aid to Gaza, and would “move to additional escalatory options” if “the American aggression against our country continues.”

Washington’s weekend strikes against the Houthis were the first since Trump’s return to the White House in January.

US National Security Advisor Michael Waltz told ABC News that Saturday’s strikes “targeted multiple Houthi leaders and took them out.”

Trump, meanwhile, Houthi warned the Houthis that “hell will rain down upon you.”

In a social media post addressed to Iran, the US president demanded the Islamic Republic stop supporting “Houthi terrorists.”