The murder of Ms Anna Lindh has sparked a debate on Sweden's relaxed attitude to security, and its emphasis on voluntary treatment for psychiatric disorders, which is a focus of the hunt for her killer.
Police have searched for the murderer among the mentally ill, and in shelters for the homeless, believing Ms Lindh's high profile in the campaign for tomorrow's euro referendum may have sparked off someone unstable and violent.
Mr Peter Eriksson, of the anti-euro Green Party, spoke of a "madman", reflecting broad belief it was the work of someone with psychological problems rather than a political conspiracy.
"The problem with people who are mentally ill is growing," said Mr Lars Leijonborg, head of the Liberal Party. While stressing it was not yet clear the killer was a patient with a mental disorder, he said: "We can see at our public meetings that people who are mentally ill interrupt the political process."
Criminal profile expert Mr Ulf Asgard said there were signs the killer was "a loner, affected by the heated euro debate".
A string of unprovoked attacks by mentally ill people has recently shocked a country regarded as safe and law-abiding.
In May, a mentally ill man drove a car at speed into a crowded pedestrian street in Stockholm's Old Town, killing two people. He said his car had behaved like a runaway horse.
The same month a 71-year-old man was beaten to death by a man with an iron bar, and last month a man injured two elderly women with a samurai sword. Both attackers had mental disorders.
Hours after Ms Lindh's death, a five year-old girl was knifed to death outside a nursery in Varmland county. A 25-year-old man who was a voluntary psychiatric patient - meaning he could move around freely in public - confessed to the crime.
No motive for the attack on the child has been established but police have not ruled out a "copy-cat" crime, especially as he had just heard of Ms Lindh's murder from hospital staff.
Some people blame reforms in the 1990s which closed psychiatric clinics and put patients in voluntary care out in society.
"Both ideological and budget reasons drove the reforms. For some patients it went well but for the most ill people it did not work at all," said Markus Heilig, associate professor at the psychiatric department of Huddinge hospital in Stockholm. - (Reuters)