LATE in the spring of 1944, having outgrown Dagmarhus, in the Copenhagen Town Hall Square, the Gestapo took over the Shell Petroleum Company’s modern office build ing in the centre of the city.
Shell House, beside one of Copenhagen’s lakes, quickly became an infamous place. Dr. Hoffmann, Denmark’s Gestapo chief, Dr. Bunke, the efficient compiler of the list of Danish Jews, and many other of the more sinister members of the occupation force were given office space there. Desks were put in the cellar for about half a dozen Danish Nazis who, under the supervision of a former Danish Army captain named Møller, laboured all day at translations of Resistance news papers and other material the Gestapo intercepted. In another basement room, loyal Danes were sometimes tortured to death. The ground floor and the next two storeys became vast records rooms, and above were offices. Only the sixth storey was empty, because it lacked a heating system, and the severe rake of its tiled roof made it cramped.
After the Royal Air Force destroyed the Aarhus University Gestapo buildings, the Germans in Copenhagen became worried. Would Shell House now be bombed? How could this be prevented?
Relying on the ability of the Resistance to learn and report every Nazi move to England, the Gestapo quickly conceived a scheme, and workmen set up flimsy concrete-block partitions to make the attic of the Gestapo headquarters into a prison. Within a week there were twenty-two small cells—five along the building’s west side, facing the lake, on the left arm of the U, and the others on both sides of a corridor along the front, on the U’s bottom. The cells’ wooden doors were plywood faced, each with five one-inch ventilation holes drilled in the top and bottom, each with a Judas window covered with a wooden flap. Each cell contained a cot, a small stool, and practically nothing else. Another six cells, quite similar, but without cots, were also built in the attic for prisoners awaiting interrogation.
Along the front hallway the Germans also put three toilets and a washroom with a mirror above each of its six sinks. There was a kitchen for the prisoners’ food.
On 11th November, before the electric heating had been installed, the first six Danes were transferred from Vester Prison to the attic. Warned they would be shot if they attempted to contact each other through the small holes that had been left for electric wiring between the cells, the prisoners nevertheless whispered from cell to cell. Taken to the lavatory whenever they wished, the Danes hid messages behind the washroom mirrors—notes explaining what questions had been asked during the interrogation sessions, and what answers had been given. A Danish charwoman named Emma smuggled letters past the S.S. guards for the prisoners, and they were at first in day-to-day touch with the Resistance organization. But when Emma was caught by the Germans and sent to a concentration camp, the prisoners had to tidy up the small cell block themselves. Even after Emma was taken away, they managed to keep abreast of the progress of the war. Their only comfort was to follow news of the Allied push along a five-hundredmile front, for all of these Danes were being tortured, and, in the end, all expected to face firing squads.
The cells were chilly, and hourly through the night the Germans turned on the lights and peered through the Judas windows to make sure the prisoners were behaving themselves. Despite this watchfulness, the prisoners learned to stand on tip-toe on their stools to squint through the cell doors’ ventilation holes to see what was happening in the corridors, and later, how to push aside the flaps on the Judas windows to look out.
The Shell House prisoners, the Germans had decided, must be the Resistance élite, and after a second group was brought in during December, the attic housed, among others, a Danish admiral named Hammerich, and Mogens Fog and Aage Schoch, both members of the Freedom Council. If Shell House were destroyed, the Germans were by then quite certain, these loyal Danes would be destroyed with it.
The Gestapo’s raids on organized resistance were increasing, and the records on the lower floors of Shell House now swelled rapidly. In December 1944 Copenhagen’s Resistance radio contacted England. In line with Hitler’s latest policy to ‘fight terror with terror’, it seemed likely that all the hostages in Shell House would be executed, anyway, so would the Royal Air Force please destroy the records in Copenhagen’s Gestapo headquarters?
This request was relayed to the Air Ministry, but when they had been told of the Danes in the attic, the Ministry would sanction no such bombing. But those men in England whose job it was to be in touch with the Danish Resistance asked Copenhagen for all intelligence data on Shell House to be sent to Baker Street—just in case.
As usual, the Danes outdid themselves, and sent London complete architect’s plans of the building, full details of its construction, and a statement of precisely what every room in the building was being used for by the Germans. All available photographs of Shell House were also dispatched, as well as a map of the surrounding area indicating the positions of other German office buildings, the use of buildings the Germans had not yet requisitioned, the placement of all German radar, anti-aircraft, and direction-finder units in the city, including those on the cruiser Nürnberg, then in the Copenhagen harbour, and even notes of the colours of all rooftops near Shell House.
Embry’s planners, assisted by Danish Major Truelsen, were given all of this material and instructed to plan a raid which, they felt at the time, would never be allowed to take place. Always there was that awful human consideration—the loyal Danes penned up in the attic.
In only a week, working from aerial photographs, from maps, and from material gleaned through questioning Danes who had recently been in Copenhagen, a scale model of the centre of the city was completed by R.A.F. model-makers. Photographs of this model would show the fliers exactly what to look for.
Again and again the Resistance radio pleaded to England for a bombing, but the Air Ministry remained adamant. Fliers competent enough to hit Shell House, it was explained, had plenty of work to do in Operation Overlord, and if for no other reason than this, Copenhagen’s Gestapo headquarters could not be bombed. In any case adverse weather made an immediate attack impossible.
The plans for the raid became more and more detailed, but new problems constantly presented themselves. When Squadron-Leader Ted Sismore looked over the material, he remarked to Major Truelsen, ‘I don’t see how it can be done. One Copenhagen street looks just like another—and all the buildings look exactly alike.’
‘Not quite alike,’ smiled Truelsen. ‘This time the Germans have helped us. They’ve camouflaged Shell House, and it’s now the only building in Copenhagen painted with bold brown and green stripes.’
One day Sismore remarked to Truelsen that the raid would be easier if he could show his squadron’s navigators a photograph of the building taken from a certain Copenhagen street corner. Sismore indicated the corner, a quarter of a mile away from the proposed target. Eight days later the wanted photo- graph arrived from Denmark via Ebbe Munck’s office in Stock holm.
The planners now grew enthusiastic, for, despite the raid’s problems, they had never worked on a plan in which they had been given so much intelligence material. But still the Air Ministry seemed to bide its time; weather conditions were still too unfavourable.
On 23rd February, the Gestapo swooped down on the Copenhagen telephone exchange to try to trap those Danes who tapped German telephone lines and who warned Resistance people when their telephones were being spied upon by the Germans. A Dane, Ove Kampmann, caught the next day as a result of this raid, was taken to Shell House for questioning because the Gestapo were fairly certain that he knew where top-level daily Resistance meetings were being held.
Not only did Kampmann know about the meetings, but he was also one of the people who attended them. It was vital, he realized, that he say nothing, and he answered no questions, even though the Germans did everything they thought might make him talk. His only chance, he decided, was to bluff the Gestapo until late Monday morning—for if he did not show up at the Resistance meeting then, his friends would know that he had been arrested, and they would change their meeting-places.
On Monday morning, when his questioning began anew, Kampmann said nothing. On the wall of the Gestapo office was a large clock, and from time to time he glanced at it, noticing the painfully slow progress of its hands, hoping that the Gestapo would do nothing that would force information from him until it was time to talk. The meeting of his Resistance colleagues would end at nine. By ten o’clock he could talk.
The Germans beat Kampmann, but he kept silent as the clock ticked on. Then, precisely at ten o’clock, he spoke up:
‘You’ll find all of them in the Technical High School.’
‘All of who?’ the Germans asked.
‘The heads of the Resistance. I don’t know their names, but that’s where they meet every morning.’
One of the Nazis, grinned broadly. ‘Thank you very much,’ he said, languidly rising from the chair he had straddled. He walked over to the wall, swung open the glass cover on the clock, and reached up to move its hands—back two hours to eight o’clock.
In the raid that followed, more Resistance leaders were captured, including Professor Brandt Rehberg, a prominent physiologist who was a key man of the organization, and also another man who headed the underground army that awaited Allied orders to emerge and give battle to the Germans.
Again a plea was radioed to England that Shell House be bombed, but again the British were not ready to attack.
A few months earlier, when the Bornholm–Copenhagen liner was on its northward voyage, it had passed as usual through a channel along the Swedish coast. There, as usual, all passengers were sealed below decks before the Swedish pilot came aboard. With the pilot was a tall dark man who sometimes was known as Major Lund. Lund entered the captain’s cabin where another man, the major’s size and build, waited. The two greeted each other, took off and exchanged their outer clothing, and then certain of their credentials. Lund remained in the captain’s cabin when the ship emerged from Swedish waters, and the other man departed with the pilot. Lund did not leave the captain’s cabin until Copenhagen, where, after the Germans glanced at his identity papers, he stepped ashore.
‘Major Lund’ was, in fact, Ole Lippmann, who had been sent from Copenhagen to London to be trained to work as England’s chief organizer in the occupied capital. Although trained as a parachutist, at the last minute it appeared safer to bring him into Denmark on the Bornholm boat, a special route for top-priority Resistance people.
Lippmann had many jobs awaiting him in Denmark, and one of the most important was to keep an eye on what, in England, was now officially labelled ‘Operation Shell House.’ He was then the only man in Denmark who knew for certain that the raid was actually in the planning stage, although many other Resistance people hoped that this might be so.
In London, the planners worked feverishly. Having decided exactly how many aircraft would be needed, what bombs must be carried, how the planes would get into and out of Denmark, the only thing lacking was the order to attack.
Once more word was sent to Resistance people in Copenhagen that, if the attack were made, probably all the Danes in Shell House attic were doomed.
Ole Lippmann weighed this warning carefully and replied that, unfortunate as the risks were, the raid still ought to be made, for the hostages were being tortured, and if they were not killed in the bombing, they still had little chance of emerging from Shell House alive. One final distressing bit of information had helped make up Lippmann's mind.
The Gestapo office telephoned the Swedish Legation in Copenhagen that the minister must come to see the Germans at once, and Minister von Dardel was ushered in to see Dr. Hoffmann. The German announced: ‘We’re very angry with you Swedes. Very, very angry—and with good reason. We’ve learned that new Swedish weapons are being brought to the Danish Resistance from your country.’
‘I’m afraid,’ the minister replied, ‘that I know nothing about it. Have you proof?’
Hoffmann ignored the question. ‘Yours is still a neutral country, isn’t it?’ he asked.
‘Yes, of course it is.’
‘Well, then perhaps you’ll be interested in these weapons. Have a look.’ The Gestapo chief placed a new sub-machine gun on his desk. ‘We’ve just captured six of these from the Resistance. – quite new, and all identical. Go on—have a look at the maker’s name.’
Minister von Dardel picked up the weapon. On it was the word ‘Husquarna’—Swedish beyond a doubt.
‘I’ll have to look into this matter. I must report it to Stockholm,’ the minister said nervously.
‘Do that,’ Hoffmann replied. ‘I’ll be interested to hear what they have to say.
After the Swedish diplomat left Shell House, one of the first persons to hear about the captured Husquarna submachine guns was Ole Lippmann. Until that moment the Danish Resistance had wanted Shell House destroyed because it was a torture house, because it contained records that would destroy them. But now they knew it also held evidence that would condemn the kind help given to them by a neighbour. Lippmann sent an urgent radio message to England, and this time the reply seemed affirmative.
Sismore’s squadron was then at a Second Tactical Air Force station at Rosières, in the Somme department of France, but they were ordered back to an aerodrome in Norfolk.
The attic of Shell House was full, not only of loyal Danes, for a quartet of informers were also housed there, trying to elicit information from the prisoners. The total number of Resistance men in the Shell House attic was twenty-five. On 1st March, after Lippmann’s final message had been sent to England, Danish Army Captain Peter Ahnfeldt Mollerup, was taken. Mollerup knew—but never told the Germans or his fellow prisoners—of Lippmann’s last message.
The day that this last prisoner was put in the attic, about seventy airmen gathered in the operations room at the Norfolk aerodrome to be addressed by Group-Captain Bob Bateson, who would lead the raid, and by Sismore and Truelsen. With them was a ‘Wing-Commander Smith’, a flier who wore no decorations, but only his pilot’s wings. ‘Smith’ had flown a Mosquito on the Aarhus raid, and he would be in the first wave to hit Shell House. He was Air Vice-Marshal Embry.
In that briefing session were some of the finest R.A.F. Mosquito pilots, men of 21, 464 and 487 Squadrons, Number 140 Wing of Two Group. The fighter pilots were also present. Together they would attempt one of the most difficult air raids of the war.
After Sismore had explained the navigational aspects of the raid, Truelsen lectured on Shell House and what went on there. The fliers were told about the men in the attic. Because of them, Truelsen said, the bombs must hit the base of the building or the pavement in front of Shell House. And because of the hostages, no incendiary bombs were being taken on the raid. The idea would be to explode the records, not to burn them. The two main staircases in Shell House were at either corner in front, at the base of the U. These would certainly be demolished, as would the one at the left rear of the building, facing the lake, but Truelsen hoped that the stairs at the back of the building, on the right side of the U, might be left undamaged. He was concerned about an escape route for the men in the attic, not for the four hundred Nazis and Danish traitors who worked in Shell House.
Should the fliers be shot down, Truelsen explained, they were to contact Resistance people who would speed them to Sweden.
Nothing seemed to have been left to chance, but the aircraft would skim in over Copenhagen’s rooftops at about three hundred and fifty miles an hour—and Copenhagen’s mass of twisting streets and identical buildings even confuse pedes trians unfamiliar with the city. To lead the raiders Truelsen had volunteered to fly in the first aircraft, but because he was an intelligence officer the British would not allow him to take part in an action in which he might possibly be captured. As Bateson’s navigator, Sismore, never having visited Denmark, was to find their way, and he had studied hard for the job.
The aircraft were to depart the morning after the briefing, and that evening the crews discussed the raid. If it worked, it would be monumental—and none of the airmen discussed what would happen if things went wrong. They knew they would be flying toward one of the most heavily defended of German positions.
The next morning bad weather again delayed the operation, but on the following morning the sky was clear and a strong wind blew across the Norfolk aerodrome. A lone Mosquito bomber taxied down the runway, rose, drew up its landing gear, and circled over the field. From the aircraft the pilot, ‘Wing-Commander Smith’, gave the order for the mission to begin. Two by two, first eighteen Mosquito bombers, then the faster twenty-eight P.51 Mustang fighters took off. Fifteen minutes later, as the Nazis and their Danish collaborators began their day’s work in Shell House, Embry and his navigator, Squadron-Leader Peter Clapham, led the fliers across the North Sea toward Jutland.