The UK navy said on Sunday that a vessel caught fire after being hit by a projectile in the Gulf of Aden.
The United Kingdom Maritime Trade Operations (UKMTO) agency, which is part of Britain's Royal Navy, said that the vessel was hit "by an unknown projectile on the aft section" at about 2340 GMT Saturday about 70 nautical miles (130 kilometres) south-west of Aden in Yemen.
The hit "resulted in a fire," the UKMTO said, adding that no casualties were reported. Damage control was under way and the vessel was proceeding to its next port of call. The agency did not provide details about the vessel hit, but advised to transit the area with caution.
The Gulf of Aden, off the Yemeni coast, links the Arabian Sea and the Red Sea. The Iranian-backed Houthi militia has repeatedly fired on merchant ships in the area since the start of the war in Gaza in October.
The Houthi militants have said the attacks are intended to support the Palestinian militant group Hamas by making it more difficult for cargo ships to reach Israel.
In late March, the UKMTO said that the number of maritime incidents in the Red Sea and the Gulf of Aden has risen by 475% since the Yemeni Houthi attacks on merchant ships began.
The route, which runs along Yemen, is one of the most important shipping routes for world trade. Freighters use it to travel from the Indian Ocean to reach the Mediterranean via the Suez Canal in Egypt. In response to the attacks, the United States and the UK have carried out several military strikes against Houthi positions in Yemen.
The European Union has also launched a military operation to protect merchant shipping in the Red Sea.