Bomb disposal experts said the device, which was washed up on a beach at Raasay, was a practice mine filled with sand.

The mine was initially thought to a real one from the Second World War.

It was a Mark 17 practice mine - they're just filled with sand

Navy spokeswoman

However, an examination carried out by the bomb disposal team from the Clyde Naval Base at Faslane, in Dunbartonshire, found it was a practice mine used in naval war games.

A Royal Navy spokeswoman said: "It was a Mark 17 practice mine - they're just filled with sand.

"They cut the top off and filled the top with a small amount of explosive and blew it up to avoid it being found by anyone in the future."

The device was found on Tuesday by the crew of a local fishing vessel on the east coast of Raasay, which is situated between the Isle of Skye and the mainland.

The area is a popular shipping route and Stornoway coastguard put a tug in position to stop vessels straying into the area while the operation was going on.

A coastguard spokesman said the mine was blown up shortly before midday on Wednesday.