Updated at 6:49 p.m. Eastern.
The three pieces of the infamous sign proclaiming "Arbeit Macht Frei" ("Work Sets You Free)" will be welded together and restored to the main gate at the former Auschwitz death camp after an improved security system is put in place to guard against another theft.
Officials at the Auschwitz memorial museum said Monday the new system would be aimed at better protecting not just the recovered sign but many other objects testifying to Nazi crimes - from two tons of human hair to a trove of written documents to the ruins of gas chambers now sinking into the earth.
"The location of the sign is its only authentic one, above the gate of the former Auschwitz I camp," museum director Piotr Cywinski said. "The sign will return there as soon as possible, after ensuring the protection of its site against damage and burglary."
Officials speculate the 16-foot iron sign they recovered, cut into three heavy pieces when it was found in a forest, may have been destined for a profitable market in Nazi memorabilia, reports CBS News Correspondent Richard Roth.
Police have not yet revealed a motive, saying they were still questioning the men. The suspects do not have known neo-Nazi or other far-right links.
"Robbery and material gain are considered one of the main possible motives, but whether that was done on someone's order will be determined in the process of the investigation," deputy investigator Marek Wozniczka said.
Rabbi Marvin Hier, founder and dean of the Simon Wiesenthal Center, said "whatever the motivation, it takes warped minds to steal the defining symbol of the Holocaust from the world's most renowned killing field."
Wozniczka said the suspects will be charged with theft of an object of special cultural value and could face up to 10 years in prison. He said other charges could be added during the investigation.
Surveillance cameras and around-the-clock foot patrols already protect the vast 940-acre (200-hectare) site - which includes Auschwitz I, where the sign was stolen, and nearby Birkenau. But museum spokesman Jaroslaw Mensfelt said it's now clear that isn't enough and that "the future security system will have to be better."
The added cost involved only adds to the museum's troubles, because it is already dealing with dilapidated structures demanding enormous preservation efforts if they are to continue to stand as a testament for future generations.
Last week, Germany pledged euro60 million ($87 million) to help preserve the site, calling it an expression of the nation's historical responsibility. But that was still only half of what Auschwitz officials say is needed.
Mensfelt said police will return the damaged sign to the museum as early as Tuesday. The sign was cut into three pieces, each containing one of the words, and the fact that the cuts were made between the intact words should make it easier to weld together, Mensfelt said. He stressed, though, that a specific plan for restoring the sign can only be made by conservation experts after they receive it from the police and analyze it for themselves.
For now, an exact replica of the sign hangs in its place.
The grim slogan "Arbeit Macht Frei" was so counter to the actual function of the camp that it has been etched into history, becoming one of the most recognizable slogans of the Nazi era. The phrase appeared at the entrances of other Nazi camps, including Dachau and Sachsenhausen, but the long curving sign at Auschwitz was the best known.
After occupying Poland in 1939, the Nazis established the Auschwitz I camp, which initially housed German political prisoners and Polish prisoners. The sign was made in 1940 and placed above the main gate there.
Two years later, hundreds of thousands of Jews began arriving by cattle trains to the wooden barracks of nearby Birkenau, also called Auschwitz II, where they were systematically killed in gas chambers.
The sign disappeared under cover of darkness in the bitter cold early Friday. Cywinski said at the time that the brazen theft could only be the work of professional thieves.
But the thieves were unable to outfox an intense, nationwide search and less than three days later, on Sunday, police arrested five Polish men they described as common criminals who were likely seeking profit from the sign found in a snow-covered forest 200 miles (325 kilometers) from where it was stolen.
Police and the museum will pay a reward of 100,000 zlotys ($34,0000) for information that led to the recovery of the sign and the arrests, police official Andrzej Matejuk said. He did not elaborate.
On the Web
Auschwitz-Birkenau Memorial and Museum: http://en.auschwitz.org.pl
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