A missile attack damaged a vessel passing through the Gulf of Aden off Yemen on Thursday, two maritime agencies and the US military said.
The Iran-backed Huthi rebels, who control much of Yemen, have carried out months of attacks on merchant vessels in the Red Sea and Gulf of Aden, disrupting the key shipping route and prompting a military response from the United States, Britain and recently France.
"A vessel was attacked by two missiles, resulting in a fire onboard," United Kingdom Maritime Trade Operations said, adding that "coalition forces are responding".
Security firm Ambrey also reported a fire aboard a Palau-flagged, British-owned general cargo ship following two missile strikes southeast of Aden.
The ship "appeared to be headed from Map Ta Phut, Thailand, and headed in the direction of the Red Sea", Ambrey said.
"Merchant shipping is advised to stay clear of the vessel and proceed with caution," it added.
While there was no immediate claim of responsibility for the attack, US Central Command (CENTCOM) said the Huthis targeted the vessel, which it identified as the MV Islander.
The attack caused "one minor injury and damage. The ship is continuing its voyage", CENTCOM said.
It added that US aircraft and an allied warship separately shot down six drones launched by the Huthis on Thursday. France said one of its frigates shot down two drones.
- 'Driving up prices' -
The Huthis say their attacks -- which they began carrying out in November -- are in solidarity with Palestinians in Gaza during the Israel-Hamas war.
They have triggered reprisal strikes on Yemen by the United States and Britain, with the Huthis responding by targeting US and British ships.
The Huthi attacks have prompted some shipping firms to take the much longer route around the southern tip of Africa to avoid the Red Sea, which normally carries about 12 percent of global maritime trade.
The UN Conference on Trade and Development said late last month that the volume of commercial traffic passing through the Suez Canal between the Red Sea and the Mediterranean had fallen more than 40 percent in the previous two months.
Egyptian President Abdel Fattah al-Sisi said Monday that revenues from the Suez Canal had "decreased by 40 to 50 percent" so far this year due to attacks on shipping.
The US State Department said Wednesday that the Huthi strikes are "driving up prices and causing delivery delays in critical humanitarian items, such as food and medicine".
"This is adversely affecting those in need of assistance around the world, including in Sudan, Ethiopia and in Yemen itself," it said.
In a bid to deter more Red Sea attacks, the European Union launched a naval mission on Monday, complementing an existing one spearheaded by the United States.
The mission -- called Aspides, Greek for "shield" -- should be up and running in a "few weeks" with at least four vessels, an EU official said last week.
On Monday, the Huthis said they had targeted three vessels, including the British-registered Rubymar, the US-owned Sea Champion and the Navis Fortuna which they described as "American."