12 April 2012 Last updated at 09:06 ET

Submarine or boat 'submerged in Lough Foyle'

Sonar images of the vessel appear to show a submarine

Environment Minister Alex Attwood has said what appears to be a submarine or boat has been identified submerged in Lough Foyle.

Mr Attwood said he had viewed sonar images of the vessel.

"I have asked that urgent work is undertaken to determine how and when the submarine or boat came to rest in this part of the lough.

"It is unusual that there appears to be no record of the circumstances behind this situation," he said.

"I have also asked that all agencies continue to work with DOE and the harbour commissioner to create certainty about the identity of and the reason why the submarine/boat is in the current location."

He said it was crucial that no diving should occur in the vicinity of the vessel.

"There may be unexploded ordnance which means there are potential risks. This may also be a war grave," he said.