Visitors walk through the entrance gate of the Auschwitz concentration camp in Oswiecim, southern Poland, in 2005. The sign over the gate was stolen in December and recovered two days later. (Herbert Knosowski/Associated Press)

A former neo-Nazi leader arrested in Sweden for his alleged involvement in the theft of the infamous Auschwitz sign can be extradited to Poland, a Swedish court ruled Thursday.

Anders Hogstrom, 34, can be handed over to Poland on condition that, if convicted, he would serve any prison sentence in Sweden, the Stockholm district court ruled. Poland agreed to the deal, a prosecutor said.

Polish investigators suspect Hogstrom of incitement to commit theft of a cultural treasure in connection with the Dec. 18 theft of the "Arbeit Macht Frei" sign at the former Nazi death camp.

Accused Anders Hogstrom during his detention hearing in Stockholm on Feb. 12, 2010. (Maja Suslin/Associated Press)

They are seeking prison terms of up to 2½ years for three Poles who confessed to stealing the sign and are investigating the role of two others.

The sign — which in German means "Work Makes You Free" — was recovered days after the theft.

Hogstrom will probably appeal the extradition ruling because he doesn't think he will get a fair hearing in Poland, his defence lawyer, Bjorn Sandin said.

Ties to extreme right

Hogstrom is said to have founded and led the Swedish neo-Nazi group National Socialist Front in the 1990s. But he left the organization in 1999 after two of its members were convicted of a high-profile police murder, and became an active opponent of the extreme right, according to Expo, a research foundation.

Reports are mixed as to what Hogstrom's possible involvement in the theft might have been.

He told one Swedish newspaper that he acted as a middleman between the Polish thieves and an English-speaking buyer. But in a video clip posted Jan. 9 on the website of another tabloid, Expressen, Hogstrom said he had simply been tipped off about the theft and tried to stop it.

Hogstrom had been detained on a European arrest warrant on Feb. 11.