A German resident held by the U.S. for almost five years tells 60 Minutes correspondent Scott Pelley that Americans tortured him in many ways - including hanging him from the ceiling for five days early in his captivity when he was in Kandahar, Afghanistan.Even after determining he was not a terrorist, Murat Kurnaz says the torture continued. Kurnaz tells his story for the first time on American television this Sunday, March 30, at 7 p.m. ET/PT.

Kurnaz, an ethnic Turk born and raised in Germany, went to Pakistan in late 2001 at age 19 to study Islam and wound up in Pakistani police custody. It was three months after 9/11, and Kurnaz says the U.S. was offering bounties for suspicious foreigners. Kurnaz says he was "sold" to the Americans for $3,000 and brought to Kandahar as terrorist suspect.

He claims American troops tortured him in Afghanistan by holding his head underwater, administering electric shocks to the soles of his feet, and hanging him suspended from the ceiling of an aircraft hangar and kept alive by doctors. "Every five or six hours they came and pulled me back down and the doctor came," he recalls. "He looked into my eyes. He checked my heart and when he said 'okay,' then they pulled me back up," he tells Pelley.

The U.S. Pentagon responding by e-mail says, "We treat all detainees humanely... and all credible claims are investigated thoroughly.... The abuses Mr. Kurnaz alleges are not only unsubstantiated and implausible, they are simply outlandish."

Kurnaz, who has told his story to European investigators, says "[It] doesn't matter whatever they will say. The truth will not change... this is the truth."

Kurnaz says he was questioned in Afghanistan about Osama bin Laden, al Qaeda and the Taliban. He answered truthfully, he says, and told them repeatedly to call the German government and verify who he was. But they continued to torture him, he says. "They used to beat me when my head was underwater...they beat me into my stomach....I had to inhale the water," he tells Pelley.

He says he was then brought to Guantanamo as one of the first "enemy combatants." His treatment there, he says, included repeated beatings at the hands of soldiers in riot gear, sleep-deprivation and solitary confinement. "It's dark inside, no lights and they can punish you in isolation... by coldness or...heat. They have special air conditioners. Very strong. They can turn it very cold or very hot."

After a landmark Supreme Court ruling in 2004, Kurnaz was visited by an American lawyer, who successfully sued the U.S. government to release his classified file. That file contained information from the FBI, German Intelligence and even the U.S. military pointing to his innocence. But after a series of Kafkaesque military tribunals and review boards, he remained in Guantanamo until 2006.

Kurnaz' lawyer, Baher Azmy, says there may be many more cases like Kurnaz's at the offshore prison. "In Guantanamo, no detainee has ever been able to genuinely present evidence before a neutral judge and so as absurd as Murat Kurnaz's case is, I assure you, there are many, many dozens just as tenuous," Azmy tells Pelley.
© 2008 CBS News