Polish authorities stepped up security checks at airports and border crossings and searched scrap metal yards Saturday as the search intensified for the infamous Nazi sign stolen from the Auschwitz death camp memorial.
The brazen pre-dawn theft Friday of one of the Holocaust's most chilling and notorious symbols sparked outrage from around the world, and Polish leaders have declared recovering the 5-meter (16-foot) sign a national priority.
The sign bearing the German words "Arbeit Macht Frei" _ "work makes you free" _ spanned the main entrance to the Auschwitz death camp, where more than 1 million people, mostly Jews, were killed during World War II.
The grim Nazi slogan was so counter to the actual function of the camp that it has been etched into history. The phrase "Arbeit Macht Frei" appeared at the entrances of other Nazi camps, including Dachau and Sachsenhausen, but the long curving sign at Auschwitz was the best known.
Police deployed 50 officers, including 20 detectives, and a search dog to the Auschwitz grounds, where barracks, watchtowers and rows of barbed wire stand as testament to the atrocities of Nazi Germany.
Spokeswoman Katarzyna Padlo said police had questioned all security guards at the site and searched local scrap metal businesses, while Dariusz Nowak, a police spokesman in Krakow, said investigators were working around the clock on the case.
The director of the Auschwitz-Birkenau memorial museum, visibly shaken by the dramatic theft, told The Associated Press he believes the theft was carried out by professionals.
"I think it was done by specialists," Piotr Cywinski said. "It was a very well-prepared action."
British historian Andrew Roberts said the sign would generate huge interest on the burgeoning market for Nazi memorabilia.
Security guards patrol the 940-acre (200-hectare) site around the clock, but due to its vast size they only pass by any one area at intervals. Cywinski said that gave thieves between 20 to 30 minutes to remove the sign and carry it off.
Museum spokesman Pawel Sawicki said the sign is made of hollow steel pipes and is believed to weigh only around 30 to 40 kilograms (65 to 90 pounds).
"A single person could lift it," Sawicki said.
Sawicki said the entire Auschwitz staff was deeply shaken by the theft. He defended security at the camp but said no one could have ever imagined thieves seizing the gate's sign.
"Thieves are also able to robs banks and museums. Clearly this was well planned. It's a blow to our human heritage," Sawicki said.
An exact replica of the sign, produced when the original underwent restoration work years ago, was quickly hung in its place Friday.
Michael Pick, 47, a history teacher from Brisbane, Australia, was glad the museum had put up a replica.
"The irony of the saying is something that we talk about in the classroom," he said, standing amid snow and below-freezing temperatures. "It would be better if it (the sign) were authentic but I would be incredibly disappointed if I showed up today and there was nothing there."
The Simon Wiesenthal Center, a leading Jewish human rights group, urged Poland to intensify its investigation and bring the thieves to justice.
"The fact is that the 'Arbeit Macht Frei' sign has become the defining symbol of the Holocaust, because everyone knew that this was not a place where work makes you free, but it was the place where millions of men, women, and children were brought for one purpose only _ to be murdered," said Rabbi Marvin Hier, the center's founder and dean.
After occupying Poland in 1939, the Nazis established the Auschwitz I camp in the southern Polish city of Oswiecim, which initially housed German political prisoners and non-Jewish Polish prisoners. The sign was made in 1940. 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 most were killed in gas chambers.
Most of the camp's victims were Jews but they also included Gypsies, Poles, homosexuals and political prisoners.
The camp was liberated by the Soviet army on January 27, 1945. Polish officials plan to mark the 65th anniversary of that liberation next month with somber ceremonies at the site.
Scislowska reported from Warsaw.