STOCKHOLM • Swedish prosecutors said yesterday they had closed their investigation into the 1986 murder of prime minister Olof Palme because their main suspect, a Swede opposed to Mr Palme's left-wing policies, was dead.

"We can't get around one person as the perpetrator. He is Stig Engstrom," chief prosecutor Krister Petersson told reporters, referring to a man dubbed "the Skandia man" in Swedish media because he was working late in the Skandia building near the shooting scene on the night of the crime.

"Because he is dead, I can't press charges against him, and have therefore decided to close the investigation," he said.

Mr Palme was killed on Feb 28, 1986, after leaving a Stockholm cinema with his wife Lisbet to walk home, having dismissed his bodyguards for the evening.

An unidentified attacker shot Mr Palme in the back and fled, leaving the 59-year-old dying in a pool of blood on the sidewalk.

Over 10,000 people have been questioned over the years, and 134 people have confessed to the crime.

Mr Engstrom was questioned as a witness early in the investigation as he was near the murder scene, but police deemed him unreliable as he had changed his story several times.

Sweden's media has suggested over the years that he changed his story to cover up his role as the gunman. He died in 2000, aged 66.

Mr Christer Pettersson - a petty criminal and drug addict - was convicted of the crime in July 1989 after Mr Palme's widow identified him in a widely criticised line-up.

But he was freed months later by an appeals court which dismissed the widow's testimony on a technicality.

Mr Pettersson died in 2004, while Mr Palme's widow passed away in 2018.

Police have never recovered the murder weapon despite testing 788 revolvers over the years, they said yesterday.

AGENCE FRANCE-PRESSE