SANAA - The US warplanes on Saturday night launched airstrikes on several Houthi sites in Yemen's capital Sanna and the northern province of Saada, killing at least 24.

Houthi-run Al-Masirah TV reported four airstrikes in the Al-Jarraf residential neighborhood in northern Sanaa and several other airstrikes on the Shoab residential neighborhood in eastern Sanaa. Later in the evening, fresh strikes hit sites in the northern part of the province's namesake central city Saada, the group's northern main stronghold. 

At least 13 civilians were killed and nine injured in US strikes on Sanaa, according to the Houthi-run health ministry. At least 11 others, including four children and one woman, were killed and 14 were injured in a US strike on Saada, Al-Masirah TV reported.

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The Houthis' political bureau described the attacks as a "war crime."

According to local residents, the strikes on Sanna targeted ammunition and rocket depots near the Houthi-controlled state television station in the Al-Jarraf neighborhood. White smoke plume could be seen rising from the neighborhood, and a series of explosions were triggered following the airstrikes, witnesses added.

Osama Sari, a Houthi official, wrote on X that the strikes on Al-Jarraf neighborhood also damaged parts of the Specialized Modern University near the Airport Road.

Another Houthi source told Xinhua that the airstrikes also targeted two houses of key Houthi leaders.

This is the first military operation conducted by the US military against the Houthi sites since US President Donald Trump assumed power in January and redesigned the group as a "foreign terrorist organization."

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Trump posted on social media Truth Social that the aerial attacks on the "terrorists' bases, leaders, and missile defenses were to protect American shipping, air, and naval assets, and to restore navigational freedom."

He also warned Houthis that if they do not stop their attacks "starting today... Hell will rain down upon you like nothing you have ever seen before."

In the meantime, the US Central Command posted footage on X showing warplanes taking off a US aircraft carrier in the Red Sea, saying that it "initiated a series of operations consisting of precision strikes against Iran-backed Houthi targets across Yemen to defend American interests, deter enemies, and restore freedom of navigation."

Following the US airstrikes, the Houthis vowed to launch retaliatory attacks, saying "this aggression will not pass without a response," and that the group is "fully prepared to confront escalation with escalation," the Houthis' political bureau said in a statement aired by Al-Masirah TV.

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On Tuesday, the Houthi group announced that it would resume launching attacks against any Israeli ship in the Red Sea, Arabian Sea, the Gulf of Aden, and the Bab al-Mandab Strait until the crossings of Gaza Strip are reopened and aid allowed in.

From November 2023 to Jan 19, the Houthi group, which currently controls much of northern Yemen including the capital Sanaa, had launched dozens of drone and rocket attacks against Israel-linked ships and the Israeli cities to show solidarity with Palestinians amid the ongoing Israel-Hamas conflict. The Houthis stopped their attacks on Jan 19, when the Gaza ceasefire deal took effect.