other services were notified of his suspicions. The failure of SOE leadership to respond to signs that the Dutch program was controlled by the Germans was probably motivated by both denial of warning signs and interdepartmental competition between SOE and the rival Secret Intelligence Service ("C") from which SOE had been created. End In the fall of 1943, two Dutch SOE agents, Pieter Dourlein and John Ubbink, escaped from Haaren concentration camp, made their way to Switzerland, and reported Englandspiel to the Dutch legation there, which passed the information along to the British government. The two agents then used one of the escape and evasion lines to get to Spain and hence to London. The Abwehr's Giskes, however, anticipated their arrival by sending a fake message, ostensibly from another SOE agent, that Dourlein and Ubbink were turncoats who became German agents. Both were imprisoned on their arrival in London and remained in a British prison until after the Normandy invasion in June 1944. They were later honoured by the Dutch government. Englandspiel was already on its last legs in the fall of 1943. The Royal Air Force (RAF), which supplied the planes and pilots for SOE, had suspended SOE flights to the Netherlands after May 1943 because of the high casualties to aircraft and airmen. The RAF had noticed that its flights to the Netherlands always arrived without opposition and that landing areas were "too bloody perfect", but planes were fired upon during their return trip to England and suffered unusually-high losses. In less than a year, 12 RAF aircraft were shot down during their return flight from SOE missions in the Netherlands. The end of Englandspiel came on 1 April 1944, with Giskes sending a taunting message to SOE complaining about the lack of recent business from England given that he had been servicing them for so long. Giskes' message also promised a warm welcome to any further agents SOE wished to insert into the Netherlands. Aftermath The fifty Dutch SOE agents that had been captured by the Germans were transported to Mauthausen concentration camp in September 1944 as allied military forces were advancing into the Netherlands, and eventually executed. Giskes, the Abwehr mastermind of Englandspiel, was arrested by the British, but after the war was employed by the United States during the occupation of Germany. Some of the officials of the Dutch government-in-exile in London refused to cooperate