Two UK warships have collided off the coast of Bahrain, the Royal Navy has said.
Social media footage appears to show HMS Chiddingfold reversing into HMS Bangor in the Gulf, sparking an official investigation.
No one on board either vessel was injured, but "some damage was sustained", the navy said.
Rear Admiral Edward Ahlgren added: "Why this happened is still to be established.
"We train our people to the highest standards and rigorously enforce machinery safety standards, but unfortunately incidents of this nature can still happen.
"I assure you that a full and thorough investigation is already under way and any changes in procedure that could prevent further incidents will be rapidly implemented.
"In the meantime the UK will continue to play a key part in ensuring the safety of merchant shipping in the region."
UK and US forces are leading an operation to ensure the safety of vessels in the region, who are being forcibly diverted away from the Suez Canal after Houthi forces began attacking them over the Israel-Hamas war.