The notorious sign spanning Auschwitz's main gate, which was stolen and cut into pieces in a 2009 heist, has been welded back together and restored almost to its previous condition, officials said Wednesday.

Conservation workers at the site of the former Nazi death camp said they have worked for nearly a year and a half photographing, analyzing and finally welding back together the pieces of the badly damaged sign bearing the cynical Nazi slogan "Arbeit Macht Frei" (Work Sets You Free).

The theft — which occurred on a bitterly cold night in December 2009 — shocked Holocaust survivors and many others committed to preserving the Auschwitz-Birkenau site and the memory of the atrocities that Nazi Germany committed there during its occupation of Poland.

"The theft and destruction of the Arbeit Macht Frei sign was a symbolic attack on remembrance," Piotr Cywinski, the director of the memorial site in southern Poland, said on Wednesday in announcing the completed restoration.

"The perpetrators nearly achieved their heinous goal, but they did not succeed."

Agnieszka Zydzik-Bialek, who led the conservation work, said the sign was in very bad shape when it arrived in her workshop. The thieves had not only cut it into pieces, they also had bent and fractured its metal tubes, she said.

Experts had to reverse not only the bent metal, but also "twisting and crushing," she said. "Many of the components were deformed, and the surface of the sign was scratched and dented."

Officials at the site said the restored sign will probably be eventually moved to an exhibition hall which is under development, but a final decision has not been made.

A replica of the sign presently stands in its place.

After the sign was stolen, police found it three days later cut into pieces in a forest on the other side of Poland.

A Swedish man with neo-Nazi ties, Anders Hogstrom, was found guilty of instigating the theft and is now jailed in his homeland. Five Poles also have been convicted of involvement and imprisoned.

Still, many questions surround the motive for the crime. There has been speculation that the group might have stolen the sign on behalf of a collector, but Polish officials investigating the case have never divulged all the details, citing an ongoing investigation.

Between 1940 and 1945 more than 1 million people, mostly Jews, were killed in the gas chambers of Auschwitz-Birkenau, or died of starvation or disease while forced to perform hard physical labor at the camp.