Prosecutors in Sweden said Wednesday they have closed the case of the 1986 murder of Prime Minister Olof Palme because the main suspect is dead.
Chief prosecutor Krister Petersson told reporters that because Stig Engstrom died in 2002, he is unable to interview him or indict him.
A gunman killed Palme after he left a Stockholm movie theater with his wife and son.
Authorities said Wednesday they had questioned 10,000 people during their probe and that more than 100 had actually confessed to the killing.
Engstrom was considered a suspect long ago, but dismissed after repeated questioning.
He had a military background, worked in an office near the crime scene, was a member of a shooting club and was known to have a strong dislike for Palme and his policies.
The lingering mystery helped spark conspiracy theories about who was responsible, with possible culprits including the U.S. Central Intelligence Agency, Kurdish militants and South African security services.