The Department of Arts, Heritage, and the Gaeltacht has ordered Ireland’s Naval Service to remove potentially dangerous mines from a German U-boat that sank off the coast of Cork in 1917.

The submarine, which is laden with mines, is located close to a gas line; the Naval Service fears that unauthorized divers might trigger a harmful explosion, the Irish Examiner said.

Over the years the Naval Service has disabled numerous World War II mines that have drifted to shore or gotten tangled in trawl nets, but this will be the first time navy divers will remove potentially unstable and aging mines from a U-boat.

The UC42 U-boat sank at the entrance to Cork Harbour on September 10, 1917 after an explosion that occurred while the crew was laying mines. All 27 crew members died.

A group of amateur divers off of Roche’s Point discovered the sunken submarine five years ago – it has been classified as a war grave, and is relatively well preserved.

During a recent inspection, the Naval Service discovered that a few seals it had placed on the U-boat had been tampered with, which sparked the fear that divers who’d gained access to the site could potentially set off an explosion.

David Stanton, chairman of the Oireachtas Committee on Justice and Defence, told the Examiner that “an ecological risk assessment would be carried out as a priority” to see if it posed a threat to any marine wildlife before commencing the operation.

“I would urge people to keep away from the submarine because of two issues — it is a war grave and people should respect that, and there is obviously a possibility that they could inadvertently trigger the mines,” Stanton said.