The US president has ordered a "powerful military action" against Yemeni-based Houthi militants

Dozens of people were killed or injured after the US launched a major airstrike campaign against Yemeni-based Houthi militants, with President Donald Trump personally observing the operation as it unfolded.

The strikes hit Yemen shortly after Trump announced a "decisive and powerful military action" against the Houthis on Saturday, warning that "hell will rain down" on them unless they cease attacking US interests and disrupting international commercial navigation in the region.

At least 13 civilians were killed in Yemen's capital, Sanaa, while ten others - including four children and one woman - lost their lives in a US strike on the northern province of Saada, according to the Houthi-run health ministry. Nearly two dozen more people were injured.

READ MORE: Trump launches 'powerful military action' against Houthis

The Houthis' political bureau condemned the attack as a "war crime," stating that "our Yemeni armed forces are fully prepared to respond to escalation with escalation."

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