Federley left his apartment in the Hammarby Sjöstad district of southern Stockholm shortly after 6pm on Wednesday evening when he was attacked by four young men.
The men, estimated to be between 20 and 25, jumped Federley, kicking and hitting him repeatedly before fleeing with his wallet.
Federley was taken to hospital in an ambulance. His wallet was later found empty.
Police have yet to make any arrests in the case and the motive behind the attack remains unknown. On Thursday, police handed the investigation over to Säpo.
“I don’t want to speculate on any motive, but that we’re taking over the investigation doesn’t mean that there is a political motive. Fredrick Federley is a member of the Riksdag and a part of the central leadership of the country and we’re responsible for his personal safety. Thus it’s natural that we take over the investigation,” Säpo spokesperson Patrik Peter told the TT news agency.
Peter added that the case has been made a priority in light of the attack taking place in the final days of the Swedish election campaign.
“Obviously it is [a priority]. We, together with the National Criminal Police (Rikskriminalpolisen) and other police agencies, place a high priority on protection of the entire election campaign,” said Peter.
Representatives from the Centre Party’s leadership were able to contact Federley, who remains in hospital, according to party leader Maud Olofsson.
She said she doubts if Federley, who has represented Stockholm County in the Riksdag since 2006, will be able to participate in the final days of the election campaign on account of his injuries.
“He took a severe beating. He has a serious concussion and a broken nose,” Olofsson told the TT news agency. “I have a hard time seeing how he can do much more in the election campaign considering the injuries he sustained.”
Olofsson is both disappointed and shocked over what happened.
“We don’t know the motive behind what happened, but regardless of what it is, something like this shouldn’t happen in Sweden,” she said.
Federley, who is openly gay, has also been interviewed by police about the incident.
“The officer who spoke with him said that he took three kicks to the head and doesn’t remember so much,” police spokesperson Tommy Jonsson told TT.
According to police, the attack may have been random.
“One witness said that the four perpetrators rode the same ferry boat between Södermalm and Hammarby Sjöstad as the witness right before the attack,” said Jansson.
No suspects have been arrested, but police are hopeful that images of whoever attacked Federley may have been captured by surveillance cameras.
Federley was an outspoken critic of Sweden signals intelligence law, the so called FRA-law, and refrained from casting a vote on the original legislation in 2007 as a way to register his discontent.
When the bill was debated again in 2008, Federley remained critical and was partially responsible for forcing the government to rework the legislation, delaying the vote by several weeks.
When the final bill was presented in September 2008, however, Federley said he was satisfied with the changes and supported the new legislation.