The Royal Navy has been called in to assist with the search for a missing Fife diver.
William Peace from Markinch has not been seen since failing to resurface while diving off the coast of Dunbar last week.
The 59-year-old was a member of an organised diving party at the site of a First World War U-boat wreck approximately three miles into the North Sea.
The alarm was raised when he failed to return and an extensive search involving the police, Dunbar RNLI and the UK Coastguard was launched.
Investigating officers are understood to have requested assistance from the Royal Navy in a bid to conclude their work.
A Police Scotland spokesperson said: “Police in East Lothian were alerted by the Coastguard around 4.40pm on Saturday July 8 after a diver failed to resurface following an organised dive.
“Specially trained officers are now leading the search for the man and we are continuing to liaise with his family to keep them fully updated on the progress of this operation.”
Mr Peace is understood to have around 30 years of diving experience, with several photographs on social media capturing him underwater.
A search and rescue helicopter joined emergency services and a local vessel, Conserver, in conducting a search of the water surrounding the U-boat wreck, however, this operation was ceased after three hours.
As efforts continue to trace the missing mariner, oceanographers are now understood to have been contacted, along with the Royal Navy.
Gary Fairbairn, the coxswain of the Dunbar lifeboat, said: “Our thoughts are with everybody involved in this incident.”