Tehran, Iran ? Iran hosted Holocaust deniers from around the world Monday at a conference examining whether the Nazi genocide took place.

The 67 participants from 30 countries included former Ku Klux Klan leader David Duke and Holocaust skeptics who have been prosecuted in Europe for questioning whether 6 million Jews were killed by the Nazis or whether gas chambers were ever used.

“The number of victims at the Auschwitz concentration camp could be about 2,007,” Australian Frederick Toben told the conference, according to a Farsi translation of his remarks. “The railroad to the camp did not have enough capacity to transfer large numbers of Jews,” said Toben, who was jailed in 1999 in Germany for casting doubt on the Holocaust.

The two-day conference was initiated by President Mahmoud Ahmadinejad in an apparent attempt to burnish his status as a tough opponent of Israel. The hard-line president has described the Holocaust as a “myth” and called for Israel to be wiped off the map.

Organizers and participants touted the conference as a scholarly gathering aimed at discussing the Holocaust away from Western taboos and the restrictions imposed on scholars in Europe. In Germany, Austria and France, it is illegal to deny aspects of the Holocaust.

Duke, a former Louisiana state representative, praised Ahmadinejad for his “courage” in having a conference “to offer free speech for the world’s most repressed idea: Holocaust revisionism.”

“In Europe, you can freely question, ridicule and deny Jesus Christ. The same is true for the Prophet Muhammad, and nothing will happen to you,” Duke said. “But offer a single question of the smallest part of the Holocaust and you face prison.”

The gathering brought quick condemnation from Israel and Germany. Israeli Prime Minister Ehud Olmert called on the world to protest, terming the conference “a sick phenomenon.”

German Parliament President Norbert Lammert protested the conference in a letter to Ahmadinejad, calling it anti-Semitic propaganda “under the pretext of scientific freedom.”

Iranian Foreign Minister Manouchehr Mottaki, whose ministry put together the conference, dismissed the criticism. “If the official version of the Holocaust is thrown into doubt, then the identity and nature of Israel will be thrown into doubt,” he said. “And if, during this review, it is proved that the Holocaust was a historical reality, then what is the reason for the Muslim people of the region and the Palestinians having to pay the cost of the Nazis’ crimes?”