Timeline: November 1943---February 1993
"At the end of November 1943, Britain's Special Operations Executive confronted a sobering situation.The Grouse team was still living on the Hardangervidda with little food, poor weather conditions and little communication with Great Britain. Forty-one British commandos were either dead or soon to be executed under Hitler's notorious Commando Order. Also, now the Nazis were aware that the Allies had targeted the Vemork hydroelectric power plant in Norway, the only source of heavy water for Germany’s atomic bomb program. After Freshman, the Germans mined and booby-trapped the hill above Vemork and had increased guards on the single-lane suspension bridge, the main route to the plant. On February 16, 1943, the members of Gunnerside parachuted over Hardangervidda. They landed in the wrong place, and were close to losing portions of their equipment. Grouse and Gunnerside found each other after a week, and combined efforts. On February 27, 1943, combined teams of Grouse and Gunnerside skied to the suspension bridge at Vemork. The men faced an enormous challenge: there was a steep, 660-foot deep gorge that the bridge spanned, which the Germans judged impassable. But, Claus Helberg of Swallow discovered a way to safely descend the gorge, cross the frozen river, ascend the other side and reach the plant by following a little-used and surprisingly unguarded railroad line. Once at the facility, they would split into two teams, one to provide cover and the other to conduct the sabotage. Rønneberg would lead the sabotage team."
Just after midnight, they crossed security. The detonation team entered the plant, placed explosives and left the plant just in time to see the success of the explosives. The explosion shattered heavy water cells and 500 kg. of heavy water flowed into the drain. No one was arrested and no lives were lost. A British rifle was left at the plant on purpose so the Germans would not retaliate and take vengence upon the Norwegians.
Heavy water production soon started again. The U.S. Air force bombed the plants stopping production of heavy water altogether. Many Norwegian civilians lost their lives. The Norwegian government in London was not informed or consulted on this action. The reason the Norwegians didn't bomb from the air is because they were afraid of civilian casualties in nearby areas. Altogether, 22 civilians were killed in the air raids, many of whom were women and children. In addition, six homes were destroyed and several damaged. The bombings led to strong reactions from Norwegian authorities.
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