Three sailors have died and others have been injured after a Houthi missile attack on a ship in the Gulf of Aden, US officials have said – the first fatalities of crew of commercial shipping since the Houthis began launching strikes at ships in waters off Yemen last year.

The officials told US news agencies that the crew of the MV True Confidence had abandoned ship after the attack, which was claimed by the Houthis.

The British embassy in the Yemeni capital, Sana’a, posted on X: “At least two innocent sailors have died. This was the sad but inevitable consequence of the Houthis recklessly firing missiles at international shipping. They must stop.”

Later US Central Command increased the toll to three.

The bulk carrier was drifting with a fire on board after being hit at about 9.30am GMT on Wednesday 50 nautical miles south-west of Aden, the vessel’s owner and operator said.

“The vessel is drifting,” the Liberia-registered owner True Confidence Shipping and Greece-based operator Third January Maritime Ltd said in a joint statement, adding that there was no current connection with any US entity.

The marine security firm Ambrey said the ship had been struck and had sustained damage, adding that a rescue operation was “under way with parts of the crew already in lifeboats”.

Houthi militants in Yemen have repeatedly launched drones and missiles against international commercial shipping since mid-November, saying they are acting in solidarity with Palestinians to oppose Israel’s military actions in Gaza.

A number of ships have been damaged in such strikes, but Wednesday’s deaths are the first among merchant sailors. Two US Navy Seals drowned in January in waters off Somalia as they tried to board an unflagged vessel carrying Iranian weapons bound for the Houthis.

The Yemen Data project estimates there have been 11 civilian casualties recorded in three separate US-led strikes against Houthi targets in Yemen in February.

The US and the UK launched Operation Poseidon Archer on 12 January. The project estimates that the number of Houthi attacks on shipping doubled in February compared with the previous month – at least 79 strikes from a minimum of 33 in January.

Wednesday’s incident came as the British embassy in Yemen warned of dire environmental consequences from the Houthi sinking of a Belize-flagged and Lebanon-owned carrier, Rubymar. The ship sank at the weekend after drifting for nearly a fortnight. Lloyd’s List said out-of-date records may have led the Houthis and the British government to view the ship as British-owned.

The intensifying disruption has led several shipping firms and oil companies to suspend or redirect voyages from the key Yemen-adjacent route, which accounts for about 12% of global seaborne transit.

Earlier this week, four out of 15 critical submarine cables in the Red Sea were cut, with HGC Communications assessing that this affected 25% of traffic.

London and Washington acknowledge they need better intelligence about the Houthis’ military assets, and are drawing up plans to help train local naval forces to assist in controlling Yemen’s territorial waters.

The Aden government is convinced that the Houthis will not end the attacks on ships in the Red Sea and the Bab al-Mandab strait even if the Israeli war on Gaza ceases.

While the militia has said it would attack vessels with links to the UK, the US and Israel, shipping industry sources say all ships could be at risk.