The robbery at Norrmalmstorg in 1973 took an unexpected turn when the hostage started sympathizing with their captors. In an instant the Stockholm Syndrome was born.
The corner at the intersection between Norrmalmstorgsgatan and Hamngatan in Stockholm was once the location for one of Kreditbanken's (The Credit Bank) offices. An August day in 1973, Jan-Erik "Janne" Olsson, on leave from prison, went in to the bank armed with submachine gun and tried to rob it. The police was on the scene right away and two officers went inside. Olsson opened fire, injuring one of them in the hand and the jaw. He then ordered the other policeman to sit in a chair and "sing something." He chose Lonesome Cowboy by Elvis Presley.
Olsson took four persons in the staff as hostage and barricaded himself in the vault. He demanded that his friend Clark Olofsson, at the time imprisoned, should be brought there and his demand was met.
A few days after the robbery attempt the police drilled holes through the wall to the vault to take pictures. Olofsson fired his gun at the forensic officers photographing and wounded one of them in the face and the hand. He threatened to kill the hostage if any attempts to release gas into the vault was attempted and he now and then forced the hostage to stand up with slip knots around their necks so that they would be strangled in case the police would give it a try. In the end they did, Olsson and Olofsson surrendered after half an hour and none of the hostages sustained any permanent injuries.
During and after the attempted robbery, the hostages showed sympathies with the robbers and criticized the police for their actions. The Swedish Prime Minister talked with the offenders and the hostage during the drama and one of the latter defended captors saying that the police had opened fire first. Some of them also insisted that the robbers should get a safe passage to the car that they had demanded. This behavior, not heard of at the time, stirred an interest in the academic world.
It was the criminologist and psychiatrist Nils Bejerot who was working for the police at the time that coined the expression "Norrmalmstorgssyndromet" (The Norrmalmstorg Syndrome). This later became known as the Stockholm Syndrome.