BERLIN, March 4 (UPI) -- Germany's freshly appointed Interior Minister Hans-Peter Friedrich has sparked controversy on the first day of his new job when talking about the role of Islam in German society.

Friedrich, who succeeds Thomas de Maiziere, now defense minister, at a news conference in Berlin said there was no proof in history "that Islam is part of Germany."


De Maiziere and his predecessor Wolfgang Schaeuble had tried to launch a debate with Germany's Muslim community to improve integration efforts.

Friedrich said he would take integration of Germany's estimated 4 million Muslims "very seriously," adding that he would continue the dialog with the Muslim community, the so-called Islam Conference.

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His statements, which weren't exactly tactful, were a repetition of his critique of a speech delivered by German President Christian Wulff, who said in October that Islam is a part of German society. Both politicians are members of German Chancellor Angela Merkel's conservatives.

On the first day of his new job, Friedrich was criticized for what the opposition and Muslim groups said were inflammatory remarks.

"Friedrich has only been interior minister for 24 hours and he starts by smashing the porcelain," Deutsche Welle Online quoted Renate Kuenast, of the opposition Green Party, as saying.

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Muslim groups said Friedrich's statement was simply wrong.

"There are a whole series of unique historic references to Islam and the Islamic world in Europe," Aiman Mazyek, the head of the Central Council of Muslims in Germany told the WAZ media group. "No one can seriously deny that."

Meanwhile, German authorities were continuing their investigation into the killing of two U.S. soldiers Wednesday at Frankfurt International.

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The suspect was identified by German police as a 21-year-old Kosovar who was living in Frankfurt. He allegedly approached a U.S. soldier waiting outside Terminal 2 of Frankfurt Airport and asked for a cigarette, police said at a news conference Friday.

He then asked whether the troops -- the others were sitting inside a bus -- were about to be deployed to Afghanistan. When the soldier said "yes," the suspect allegedly killed him with two shots to the back of his head. Police said he charged into the bus and killed its driver with two shots to the head, seriously injuring two other soldiers. A fifth soldier escaped unhurt only because the gun failed to fire twice when it was pointed at his head.

The suspect then fled into the terminal and was overwhelmed by one of the soldiers and German federal police.

Authorities say they believe the suspect acted alone and was motivated by his personal hatred and radical Islamist convictions.

Frankfurt and nearby Ramstein Air Base have in the past been targets in attack plans by terrorists. German police in 2007 arrested three militants who had planned to attack U.S. targets in Germany -- among them Ramstein Air Base and several bars frequented by U.S. troops -- to kill hundreds, possibly thousands of American troops.