[2] On the night of August 18, 1972, between 3 a.m. and 4 a.m., 15 inmates escaped from the Kuma bunker, which was considered the most escape-proof prison in Sweden.
One of the factors contributing to the success of the escape was that the security department was not monitored by guards around the clock.
[4] The police were able to establish early on that the 15 cell doors had not been broken into, but had been opened with a key.
In order to open the doors, an inmate managed to fool the guards that he was already locked up.
A total of 20 cells were opened, but five inmates chose to stay behind, partly because they had little time left before their release.