The institution inmates were locked into the bunker with the explosive charges, the Jewish men into the other. The area was sealed off so that the »experiment« could begin. In Nebe's refuge the detonator cables were activated, then there was a short explosion. The desired effect had not occurred as expected. While the wooden roof had collapsed and the door had been blown open, half of the patients crawled or ran out of the bunker in panic, screaming loudly. While Jewish forced laborers had to catch the surviving patients in the twilight, Widmann and his companions analyzed their errors. They concluded that the explosive charge had been too weak, and a second attempt was undertaken. After this explosion the refuge collapsed completely, and there was no longer any noise. Several parts of the victims' corpses were hanging in the trees. Now the hole in the ground should have been filled-in by the Jewish ghetto inmates, but these had managed to flee in the general confusion.