Sultan Sabha, 40, had hired a private boat with a friend so that they could explore the WW2 German submarine U533, which lies 25 miles off the coast of Fujairah in the United Arab Emirates.

According to the National, the pair had carried out an 18-minute dive and were starting their ascent when Sabha’s camera became entangled in line.

The diver’s brother Diaa told the paper that Sultan Sabha had 22 years’ experience and was a technical wreck- and cave-diver who trained every week. He had had been planning a trip to dive the deep Boesmansgat caves in South Africa.

Simon Nadim, Manager of Fujairah’s XR Hub dive-centre, found the camera in mid-May while searching for Sabha, and passed it to the authorities.

Diaa claimed that, although the camera was thought likely to provide clues to what happened, police were not sharing information with the family. In the absence of a body, Sultan’s relatives refused to accept that the diver was dead.

Sultan, who had been living in the UAE for 18 years, owned a club in Dubai.

U533 was bombed by a British aircraft while it was charging its batteries at the surface on 16 October, 1943.

Part of a fleet of 30 U-boats sent to the Indian Ocean during WW2, it had been assigned to intercept US tankers carrying crude oil from Kuwait.

Divers discovered the wreck in 2009.

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