DUBAI, United Arab Emirates — U.S. airstrikes targeting Yemen’s Houthi rebels pounded sites across the country overnight and into Monday, with the group saying the one attack in the capital killed at least one person and wounded more than a dozen others.

The American strikes on the rebels, who threaten maritime trade and Israel, entered their 10th day without any sign of stopping. They are part of a campaign by President Donald Trump targeting the rebel group while also trying to pressure Iran, the Houthis’ main benefactor.

So far, the U.S. has not offered any specifics on the sites it is striking, though Trump national security adviser Mike Waltz claimed the attacks have “taken out key Houthi leadership, including their head missileer.” That’s something so far that has not been acknowledged by the Houthis, though the rebels have downplayed their losses in the past and exaggerated their attacks attempting to strike American warships.

“We’ve hit their headquarters,” Waltz told CBS’ “Face the Nation” on Sunday. “We’ve hit communications nodes, weapons factories and even some of their over-the-water drone production facilities.”

An apparent U.S. strike Sunday hit a building in a western neighborhood of Yemen’s capital, Sanaa, killing at least one person and wounding 13 others, the rebel-controlled SABA news agency said, citing health officials. Video released by the rebels showed the rubble of a collapsed building.

A building next to the collapsed structure still stood, suggesting American forces likely used a lower-yield warhead in the strike.

The Houthis also described American airstrikes targeting sites around the city of Saada, a Houthi stronghold, the Red Sea port city of Hodeida and Marib province, home to oil and gas fields still under the control of allies to Yemen’s exiled central government.

The campaign of airstrikes targeting the rebels, which killed at least 53 people immediately after they began March 15, started after the Houthis threatened to begin targeting “Israeli” ships again over Israel blocking aid entering the Gaza Strip. The rebels in the past have had a loose definition of what constitutes an Israeli ship, meaning other vessels could be targeted as well.

Meanwhile, the United Nations said Monday it will “reduce its footprint” in the Gaza Strip after an Israeli tank strike hit one of its compounds last week, killing one staffer from Bulgaria and wounding five other employees.

The world body will temporarily remove about a third of its 100 international staffers working in Gaza, U.N. Secretary-General spokesman Stéphane Dujarric said. He pointed to the increased danger after Israel relaunched its military campaign last week.

Dujarric’s statement was the U.N’s first to point the finger at Israel in the Wednesday explosion at the U.N. guesthouse in central Gaza. He said that “based on the information currently available,” the strikes on the site “were caused by an Israeli tank.”

Israel’s military repeated its denial that it was responsible for the strike.