Resistance Fighter Who Thwarted Nazi Nuclear Ambitions Dies at 99

Norwegian prime minister calls Joachim Roenneberg 'one of our great heroes'

File photo: WWII Norwegian resistance fighter Joachim Roenneberg holds up a Union flag after it was presented to him by the Clerk of the House of Lords in Westminster, London, 2013.
REUTERS/Andrew Winning/File Photo

Joachim Roenneberg, the leader of a daring World War II raid to thwart Nazi Germany’s nuclear ambitions died Sunday in his home country of Norway at the age of 99, Norwegian government officials said.

Born in 1919 in the town of Aalesund, Roenneberg left Norway in 1940 following the Nazi invasion. He went to Brtain, where he joined a special commando unit operating under the British Special Operations Executive. 

Roenneberg, serving behind enemy lines in his native Norway during the German occupation in 1943, blew up a plant producing heavy water, or D2O, a hydrogen-rich substance that was key to the later development of atomic bombs.

Picked by Britain’s war-time Special Operations Executive to lead the raid when he was only 23 years old, Roenneberg was the youngest member of Operation Gunnerside, which penetrated and destroyed key parts of the heavily guarded Norsk Hydro plant.

The subject of books and documentaries as well as movies and a TV drama series, notably “The Heroes of Telemark,” a blockbuster from 1965 starring Kirk Dougles. The attack took place without a single shot fired.

To Roenneberg’s team, however, the stakes could not have been higher. An earlier raid failed to even reach the site, with dozens of attackers captured and killed, and Gunnerside members later described their own assault as a near-suicide mission.

They didn’t have a plan, Roenneberg later told the New York Times: they winged it. 

Parachuting onto a snow-covered mountain plateau, the small group teamed up with a handful of other commando soldiers before skiing to their destination, penetrating the plant on foot and blowing up the heavy water production line.

Describing a pivotal moment, Roenneberg later said he made a last-minute decision to cut the length of his fuse from several minutes to seconds, ensuring the explosion would take place but making it more difficult to escape.

While a manhunt ensued, the group fled hundreds of kilometers across the mountains, with Roenneberg skiing to neighboring Sweden, a neutral country in the war, two weeks later.

At the time, he hadn’t even realized the plant was part of the Nazi nuclear program, Roenneberg said. 

While historians doubt that Adolf Hitler’s Germany would have been able to produce a nuclear weapon in time to stave off defeat, they also recognize that the risks were much harder to quantify in 1943.

After Gunnerside, Roenneberg participated in other missions. He became a radio reporter following the 1945 liberation, but rarely spoke of his wartime achievements. Later in life he gave speeches and lectures well into his nineties, warning against the destructive force of totalitarianism.

Norway’s Prime Minister Erna Solberg on Sunday praised Roenneberg for his work both during and after the war.

“He is one of our great heroes,” she told news agency NTB.