Geurt van der Zalm, Maarten Noordzij and Piet Oosterlee were trying to get air in their inflatable boat on 22 October 1944 to carry intelligence and a few men, including a courier, across the river Waal. The Waal crossers were unexpectedly surrounded by German soldiers. They were marched off to the so infamous Juliana School on Grotebrugse Grintweg, in those days the headquarters of the occupiers in Tiel.

The school served as the prison of the Wehrmacht led by Tiel's notorious Ortskommandant, Hauptmann Martin Richter. Piet Oosterlee, in a desperate attempt to escape the next morning, Monday 23 October, jumped out of the window of the interrogation room, which was located in a villa adjacent to the school. He was promptly shot dead by a German guard. What exactly happened to Piet's body is unknown. The other two men were presumably executed the same day; it's unknown what exactly happened to them.

The the memorial plaque was initiated by Nelleke van Eck, a great niece of the killed Maarten Noordzij. Text and photos were collected by Emile Smit and the sign was manufactured by Bas Reijnen.