ADEN, Yemen - Britain on Sunday reported that at least four crew members from the Liberia-flagged ship Eternity C were killed in Red Sea attacks by Yemen's Houthi group last week, with several others still missing.

In a statement posted on social media platform X, the British Embassy in Yemen condemned the "unjustified Houthi attacks" on the Liberia-flagged ships Magic Sea and Eternity C, and called for the "immediate and unconditional release of all crew members of the Eternity C."

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While the exact number of missing personnel was not disclosed, the embassy stressed that the attacks constitute "a violation of international law and freedom of navigation," warning that continued Houthi assaults on commercial shipping risk further destabilizing the region and undermining efforts toward sustainable peace in Yemen.

Both ships were operated by Greek companies and were allegedly targeted because the Houthis claimed they were bound for Israeli ports, according to earlier announcements by the Houthi group.

The strikes are part of the Houthis' ongoing maritime campaign in the Red Sea against ships they claim are linked to Israel, which the group says is a response to the ongoing conflict in Gaza.

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In a televised speech Thursday, Houthi leader Abdulmalik al-Houthi reaffirmed his commitment to maintaining what he called a "ban on navigation of the Israeli enemy" in Red Sea waters.

As of Sunday, the Houthis have not immediately responded to the British statement nor confirmed the detention of crew members from either vessel.