The assassination of Olof Palme

The Prime Minister of Sweden Olof Palme was assassinated on 28 February 1986 while returning from the theater.
There have been some versions of murder. In the operation accused the Kurdistan workers party, extreme right-wing Northern state party, the European labor party and the world anti-Communist League (WACL), there was the version about participation in murder of Carlos the Jackal spoke version about participation in murder of South African racists, and the connection of this murder with the operation of the supply of arms to Iran (the "Iran – Centras"). Neither of these assumptions were not confirmed.
The only one brought to trial - the version about participation in murder of drug addict and criminal Christer Pettersson, who is believed to revenge thus to the government for a jailed friend.