Consular support is being provided to “a number of British nationals and their families” after a tourist yacht sank in the Red Sea off Egypt, the Foreign Office said.
There are reports that four Britons were on board the vessel south of the coastal town of Marsa Alam and two of them remain missing.
Amr Hanafy, governor of the Red Sea region, said the yacht was carrying 31 tourists and 14 crew.
Twenty-eight people were saved by rescuers.
A spokesperson for travel trade organisation Abta said: “We have been in contact with our members to see if they had any customers on the ship affected by this incident.”
A distress call was made from the yacht shortly before dawn on Monday.
The vessel had left Marsa Alam for a five-day sailing.
It was not immediately clear what caused the sinking.
The Egyptian Meteorological Authority warned of high waves on the Red Sea and advised against maritime activity on Sunday and Monday.
The yacht was operated by Dive Pro Liveaboard, which is based in the Egyptian resort of Hurghada.
The company said it has no information on the matter.
Rescue operations are being co-ordinated by the Egyptian military and the Red Sea Governorate.
Armed forces aircraft were deployed above the scene as part of the response.
Marsa Alam is a popular destination for tourists embarking on diving holidays, as it is near large areas with coral reefs.
Three Britons died in June last year when the diving boat they were on burst into flames off Marsa Alam.
The fire was caused by a suspected electrical fault.
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