Twenty-five years have passed since Swedish Prime Minister Olof Palme was gunned down on an icy sidewalk in central Stockholm, but with no end to the probe in sight, the murder remains an open wound in Sweden.
"It has been a very long time since it happened, but at the same time, it feels like it is still very close," says Joakim Palme, who was 27 when his father was shot and killed on February 28, 1986.
"It is very difficult that there has never been any judicial end point, or closure," he told AFP.
Behind a red, double-vaulted door several floors underground in the Stockholm police headquarters, 225 metres of bookcases that line the concrete walls filled with 3,600 folders make up the archives on the investigation so far into the murder.
According to Stig Edqvist, who has led the Palme murder investigation for the past 14 years, around 130 people have confessed to the crime and some 450 guns have been test shot to see if they match two bullets found at the scene.
Hundreds of thousands of tips have come in over the years and a handful keep coming in each week on the case, which would have been filed away for good Monday if Sweden last year had not scrapped its 25-year statute of limitations on murder.
"We have to be realistic. After 25 years, it is obviously a difficult case to solve, but I still hope we will manage," Edqvist says standing between rows of neatly tagged brown cardboard folders.
Gunnar Wall, a journalist who has written two books about the case, is harsh in his assessment.
"After 25 years of investigating this, basically we still know nothing," he laments.
Palme did not have a bodyguard with him on the night he and his wife Lisbeth were walking along the busy Sveavägen towards their home in the Old Town after a spontaneous trip to a downtown Stockholm cinema.
A gunman came up from behind and shot him twice in the back. Lisbeth was also grazed by a bullet.
The man ran off, taking his .357 Magnum revolver with him and leaving Palme in a pool of blood on the snow-covered sidewalk at the corner of what has since been renamed Olof Palme Street. The gun has never been recovered.
The murder sent shockwaves through Sweden, which is often said to have "lost its innocence" that day.
"The murder changed the way we perceive politicians," says Jens Orback, the head of the Olof Palme International Centre.
"Olof Palme said once he wanted to be listed in the telephone catalogue just like everyone else... to connect with people without being encircled by guards. But as we have seen, that is not always possible," he tells AFP.
That trauma of Palme's murder was relived again in 2003 when Sweden's hugely popular foreign minister Anna Lindh was stabbed to death while shopping -- also without bodyguards -- at a Stockholm department store by a man with a history of mental illness.
"A certain innocence has been lost," says Wall, pointing out that "people no longer expect as much from police or the courts."
The Palme investigation was a mess from the start.
"A lot went wrong," acknowledges Edqvist, pointing out that the attempts to cordon off the murder scene "were ridiculous."
News footage from the time shows shocked and crying onlookers crowded almost within touching distance of the red-stained snow, with a mountain of roses towering nearby.
Then there was the politically-connected police chief with no experience investigating murder initially placed in charge of the probe.
"I think the government wanted him in charge because they were worried sensitive information would emerge," Wall says, pointing out that "Palme was very controversial."
A left-wing activist in his youth, Palme infuriated Washington with his outspoken criticism of the US war in Vietnam.
He backed communist governments in Cuba and Nicaragua, spoke out against apartheid and nuclear power, and advocated redistribution of wealth, and some charged he was paving the way for a Soviet invasion of Sweden.
Investigators suspected the Turkish Kurd rebel group PKK, the Swedish military and police and the South African secret service, but were accused of dragging their feet on leads that could damage Palme's reputation, including the possible connection to his role in a major weapons deal between Swedish company Bofors and the Indian army.
Palme's family meanwhile remain convinced they know who did it.
Christer Pettersson, a petty criminal and an alcoholic and drug addict, was identified by Palme's widow in a widely-criticised line-up nearly three years after the murder, and was convicted of the crime in July 1989.
He was however set free months later by an appeals court due to lacking evidence, and the Supreme Court never agreed to hear the case against Pettersson, who suddenly died in 2004.
"I myself am convinced beyond a reasonable doubt that it was Christer Pettersson," Joakim Palme tells AFP, saying of all the disappointments in the case, he is most upset that the courts failed to convict Pettersson.
"It is devastating that no one was ever punished for such a serious crime," he says.
AFPs Nina Larsson