A 19-year-old British snorkelling instructor has died while swimming underwater off the Greek island of Zakynthos.
Harry Byatt failed to surface after diving into the sea, his employers said.
He had been as an instructor at the Peligoni Club, the BBC reported. Staff at the club raised the alarm five minutes after he started swimming using a monofin and a mask.
CPR was administered on the rescue boat after Mr Buatt had been found unconscious, but doctors and paramedics were unable to resuscitate him.
A Foreign Office spokesman said: “We are supporting the family of a British man who died in Zakynthos, Greece and are in contact with the local authorities.”