The incident took place on Saturday. The man was diving with friends, RUV reported. The friends alerted the emergency services to the fact that they had lost sight of the man underwater early on Saturday.
The ensuing search involved boats, a helicopter and divers. Rescuers succeeded in finding the man at around 09.30 and transferred him quickly to a Danish hospital — doctors were unable to revive him, however.
The deceased Icelandic diver was resident in Sweden. Police have yet to make his name public.