> The Houthis also hit at least one Israeli-linked commercial vessel in the Indian Ocean, some 300 miles east of the coast of Africa, in late April, and have claimed to have staged several other attacks on ships there.

On May 3, Houthi spokesperson Yahia Saree warned the campaign would soon target vessels sailing to Israel from the Mediterranean, while vowing to expand attacks in the Indian Ocean.

"There's really no precedent for the use of anti-ship ballistic missiles, the way they are doing it," the senior US defense official said, adding, "It's a kind of maritime terrorism that the entire world has an interest in seeing brought to a close."