Roy Nielsen Roy Nielsen ( 27 March 1916 – 4 April 1945 ) was a Norwegian resistance member during World War II , a member of Milorg and involved in propaganda and sabotage . Among his sabotage operations was the destruction of 25 Messerschmitt fighter aircraft and 150 engines stored in a bus garage in Oslo , on 14 August 1944 , together with Max Manus , Gunnar Sønsteby and others . Together with Max Manus he succeeded in sinking the German troop ship SS " Donau " in the Oslofjord 16 January 1945 , by placing magnetic limpet mine s with time delay on the ship ' s side . Personal life . Nielsen was born in Kristiania as the son of Christian and Signe Nielsen , and he married Helen Næss in 1941 . He was an active amateur boxer in the club Fagforeningenes IF av 1926 . World War II . Sabotage . During World War II he was a member of the armed Norwegian resistance organization Milorg . He cooperated with Kompani Linge soldier Max Manus in the SOE " Operation Bundle " , sabotage missions directed towards German ships . The group experimented with home - made torpedoes . An attempt to hit a troop ship in Oslofjord was a failure , but a later attempt , in summer 1944 , to hit a destroyer outside Moss was a partial success , as the ship was seriously damaged and out of action for seven months . Operation Bundle ' s greatest success was the sabotage against the German troop ship SS " Donau " in Oslofjord in January , 1945 . The intelligence organization RMO managed to find a weak point in the German guarding of the ship during docking time . From beneath a defunct goods lift in a building on the pier it was possible to reach the sea , by making a hole in the floor . A rubber boat and equipment was smuggled in by Alf Borgen in advance , and Nielsen and Manus came by to inflate the rubber boat some days before the arrival of SS " Donau " . When the ship arrived on 15 January , Nielsen and Manus simply walked into the pier area , passing the control point with ease as Nielsen deliberately slipped and fell right outside the gate . The two then entered the building , climbed down into the rubber boat , and placed ten limpet mines onto the side of the ship . One limpet mine was placed on a smaller vessel " Rolandseck " . During the sabotage Nielsen and Manus were kept safe by undercover pier worker Kåre Halvorsen , who also had made the hole in the floor . The bombs went off at 2300hrs when " Donau " was outside Drøbak , instead of in open sea as planned , and the captain managed to beach her . Later during the night " Donau " slipped off land and into somewhat deeper waters before settling . After the explosions on " Donau " the Germans feared that saboteurs had placed limpets on more ships and towed " Rolandseck " away from the pier and searched the ship side from rowing boats . No explosives were found and the loading of " Rolandseck " continued from a short time until the limpet exploded . The Germans were prepared for such a possibility and plugged the resulting hole with a large mat , saving the ship and allowing her to later be placed in dry - dock . On 14 August 1944 , Nielsen initiated the sabotage against the Luftwaffe ' s depot at Bjølsen , where the Luftwaffe had confiscated part of a bus garage belonging to Oslo Sporveier . The depot had been moved there from Kjeller in fear of air strikes . Nielsen extracted information about the location from a contact in Oslo Sporveier , and also came along due to Gregers Gram ' s stay in Sweden at the time . The saboteurs sneaked into Oslo Sporveier ' s part of the garage , and stole keys from a night watch without drama . Nielsen kept guard in the night watch office ; the other participants were Max Manus , Gunnar Sønsteby , Andreas Aubert , Henrik Hop , William Houlder and Erik Hansen Bakke . of plastic explosive s , carried to the garage in four suitcases , and a sack with of dynamite were detonated . There was a fire lasting three days in which the Luftwaffe lost 25 Messerschmitt Bf 109 ' s , 150 aircraft engines and their largest store of spare parts for fighters in Norway . Nielsen was also in charge of the sabotage of Arbeidstjenesten ' s office in " Wergelandsveien 3 " . He obtained a copy of the door key ( via an imprint in plastilina ) together with Dick Zeiner - Henriksen , but the actual sabotage mission was called off because there were people present at the office . Propaganda . Nielsen came to be one of the leaders of the propaganda organization Operation Derby when it was reorganized after the death of Gregers Gram in November 1944 . Operation Derby initially focused on black propaganda directed towards German soldiers , but they also issued the undercover magazine " Fritt Land " , and distributed the bi - weekly magazine " Håndslag " ( produced in Sweden ) and the monthly magazine " Det frie Norge " ( from the Norwegian government in London ) . Death . On 4 April 1945 a German crackdown against Operation Derby took place . The home of Kolbein and Kari Lauring was surrounded by German forces , whereupon Kari telephoned Max Manus who in turn notified other resistance members . All resistance members would need to go in hiding at various cover - up apartments scattered around the city . Nielsen went to the address " Bygdøy allé 117 " , to what he assumed to be a safe house , but was surprised by German forces there and fatally shot while escaping . The same thing had happened to fellow resistance fighter Olav Ringdal earlier that day . Kolbein Lauring and Manus managed to escape from their respective locations , whereas Kari Lauring was arrested .