According to Clissmann, the initial December 1940 recruitment pool from the entire Stalag network was just over one hundred POWs, with each claiming to be of Irish nationality, and the number of officers was under five. The five officers made it clear that they would only fight in the event of an invasion of Ireland by British troops (this was being planned as Friesack recruitment took place, see Plan W). In Spring 1941, when Dr. Jupp Hoven, who was considered an expert on Irish affairs because of his time in the country before the war, arrived at Friesack, he found a recruiting base of eighty Irish POWs. This was eventually weeded down to a mere ten POWs who the Germans felt were sincere in their desire to fight for Germany. In order to keep their agreement to work for the Axis secret from their fellow prisoners, a prison break to spirit Codd and Stringer (see below) from the camp was arranged in mid-September 1941. and they were taken to Berlin to take up training by "Abwehr II". In Berlin they were accommodated in a house. Just before Christmas 1941, Brady, Cushing, Murphy, O'Brien and Walsh (see below) also left Friesack and were taken to Berlin by the Germans.