AN unexploded World War 2 bomb discovered in the sea near Wemyss Bay contained 350kg of explosives, it has been revealed.

The Royal Navy said that the 'pristine' German-laid mine was discovered on the channel by the crew of a Marine Scotland research boat last week.

The lifeboat were called to help safely evacuate seven crew members before the vessel was sailed to Ettrick Bay on the Isle of Bute.

A controlled explosion then took place on Thursday involving bomb disposal experts.

Lieutenant Commander Mark Shaw, Commanding Officer of of the Royal Navy's Northern Diving Group, described the submarine-laid mine as being in 'remarkable condition' considering it had been sitting in the Clyde for 80 years.

He said: "From the initial pictures, we were able to easily identify the mine type and importantly determine that the explosive fill was intact and therefore presented a significant hazard.

"This highlights the remaining presence of historic ordnance. Even small items can be unstable and present an explosive hazard.

"Carrying-out a controlled explosion is the only safe way of dealing with them and neutralising the hazard."

He said that anyone who comes across a suspected piece of ordnance should not interfere with it and immediately contact the emergency services.