The term was defined by an American psychiatrist, Frank Ochberg, who researched the 23 August 1973 robbery at Kreditbanken in which a romantic relationship developed between one of the captors and a hostage.

"The party has just begun!" yelled 32-year-old robber Jan-Erik Olsson as he entered the bank mid-morning and fired off a round from his sub-machine gun.

He took four bank employees hostage, demanded three million kronor, weapons, and an escape car. Most importantly, he demanded that Clark Olofsson, a heavy-duty criminal serving time in prison, be released and brought to the bank, a request which was met.

The siege ended after six days when police gassed the bank and the robbers gave up. To the surprise of many, some of the hostages, including 23-year-old Kristin Enmark, physically protected the robbers as they left the bank, to ensure police wouldn't fire on them.

Compassionate feelings

Ochberg, an expert who worked with the FBI, was serving on a national task force on terrorism and disorder set up by the US Attorney General's office after 11 Israeli athletes were executed by a Palestinian group at the 1972 Munich Olympics.


"To try to have a mutual understanding in that kind of situation is not so strange, it's a method of survival"

Kristin Enmark, Stockholm hostage

As part of his research, he decided in 1976 to delve into the events surrounding the Stockholm bank robbery to explain how the hostages could develop warm, compassionate feelings for their violent, armed captors.

"The remarkable behaviour of hostage Kristin, her affection for her captor, his reciprocal affection for her and her anger at the authorities became the basis for my definition of the syndrome," Ochberg told Agence France Presse by telephone.

"The syndrome begins with shocking and sudden capture, terror and infantilisation (where) you cannot eat, talk, move or use a toilet without permission," he explained.

"But then somebody gives you permission to talk and eat and move, and live," he said. The gift of life "results in primitive, primordial gratitude" which is the foundation for all future feelings of love, he said, recalling the semen traces found on the floor of the bank vault.

"To try to have a mutual understanding in that kind of situation is not so strange, it's a method of survival," Kristin Enmark once said.

But Ochberg begs to differ, insisting that "it is not a reflex for life" but rather "a sense of gratitude".

In fact in some cases, as with Kristin and her captor, victims and hostage-takers continue their relationship even though the victim's life is no longer at risk.

Despite many rumours to the contrary, Kristin did not marry her captor though they did remain friends.

Fourteen Europeans released in Mali this week after being held captive for six months by Algerian Islamist fighters in the desert, while not showing classic Stockholm Syndrome symptoms, did show a certain sympathy with their captors.

"They insisted over and over again that they did not see us as enemies and regretted they had to hold us captive ... They always said they would not kill us," one said. 

Brainwashed

James Kilgore, member of the gang that kidnapped Patty Hearst

In the most famous case of the Stockholm Syndrome, Patty Hearst, the granddaughter of publishing baron William Randolph Hearst, was kidnapped by the leftist Symbionese Liberation Army in 1974. She robbed a San Francisco bank together with her captors and was brainwashed into denouncing her capitalist roots.

Hearst was sentenced to seven years in prison for armed robbery, but had her sentence commuted by President Jimmy Carter.

William Sargant, a British expert in mind control who interviewed Hearst before her trial, concluded that a person whose nervous system is under constant pressure can display "paradoxical cerebral activity", that is, bad becomes good and good becomes bad.

In the late 1970s, Ochberg sought to promote the Stockholm Syndrome to help save lives in hostage-taking situations, and convinced the FBI to apply his theories and spread them abroad.

Practical application

They were put to use in 1977 when Moluccan separatists held a school and train hostage in the Netherlands.

"We wanted the captor to take the pulse of a sick hostage, in order to establish a 'touching relationship'," he said, stressing that the captor's reciprocal attachment to the hostage is key to developing a relationship.

That attempt failed however when a doctor among the passengers volunteered. Two hostages and six terrorists were killed in a final offensive after a 19-day siege.

According to Ochberg, the Stockholm Syndrome can also be diagnosed among women who suffer from spousal abuse and journalists who cover conflicts.