The family of late Swedish prime minister Olof Palme has filed a complaint for slander with judicial authorities over a film that shows a character similar to the leader assassinated in 1986 going to a brothel, Swedish media reported Friday.

"I think spreading rumours without any substance is unacceptable, accusing (my father) of serious crime, of paedophilia and molesting a minor," Maarten Palme told public broadcaster SVT.

The film "Call Girl" is based on a political scandal in the 1970s, when daily newspaper Dagens Nyheter claimed to have seen a secret police memo to Palme alleging that he had gone to a brothel where he had sex with an underaged prostitute.

Palme denied having received the letter and the paper was fined over the story, but the memo was made public in 1991.

Palme's son Maarten refuted claims by director Mikael Marcimains that the film is a work of fiction.

"The film includes scenes that clearly convey. . . that Palme paid for sex with a 14-year-old prostitute," he said.

Palme was shot dead by a lone gunman on the evening of February 28, 1986, shortly after leaving a cinema in central Stockholm to walk home with his wife Lisbet.

The murder has never been solved despite hundreds of thousands of leads over two-and-a-half decades.

Sweden in 2010 scrapped its 25-year statute of limitations on murder, and the investigation continues.