ROYAL Marines from Plymouth halted a winter training exercise in Norway because the temperatures dropped to an incredible minus 40 degrees.

A group from Turnchapel-based 539 Assault Squadron was due to visit a firing range in Elvegardsmoen in northern Norway on Wednesday morning as part of Exercise Lupus, but an advance party called off the planned drill after recording a still-air temperature of minus 18 with 50mph winds, which brought the temperature down to minus 40 degrees.

While the young marines completed cold-weather warfare courses last month to deal with Arctic conditions, officers said they didn't want to risk injuring them on a training exercise.

Cold-weather warfare specialist Sgt Simon Jones, attached to the squadron, said: "If you injure them here, you take them away from a deployment which could be just around the corner.

"There are real dangers training in these temperatures."

Sgt Jones, a Mountain Leader 1, said working guidelines mean commando training stops in combined air and wind-chill temperatures of minus 30 degrees or less. After that it's a judgement call by a Mountain Leader as to whether training continues.