Speaking with The Anadolu Agency in an exclusive interview, Murat Kurnaz, a German citizen of Turkish descent, reminded that Obama's major election campaign pledge "was to close Guantanamo" before he was elected as president in 2008.
"He has not closed Guantanamo after he was elected the first time. He has not closed the prison after being elected for the second time either," said 32-years-old Kurnaz.
"If the president would have kept his promise, there would be no such thing as Guantanamo," he said.
Kurnaz traveled to Pakistan to improve his Islamic knowledge in 2001 shortly after the 9/11 attacks. However, he was arrested by Pakistan's security forces with no explanation on November 2001 when he was 19 years old.
Kurnaz was then sold to U.S. forces for a bounty of $3.000, and brought to U.S. military base in Kandahar before his transfer to Guantanamo.
"What happened in Guantanamo was preposterous. So many detainees were killed under torture, which I also was subjected to," he said.
"There were children who were 9-12 years old among us. So many detainees were 14 years old. The oldest detainees were 86-87 years old," he added.
"They have treated the old and youth detainees similarly. They have tortured both young and old detainees. If they did not give food to youth, they did not give any food to old detainees, either," said Kurnaz.
Kurnaz also said that he learned five different foreign languages in Guantanamo prison because there were only a few people who could speak Turkish.
"I have prayed to Allah for patience. Thank goodness! Allah has given the patience to me," he stressed.
Kurnaz was released from Guantanamo by the help of German Chancellor Angela Merkel who requested then-President George Bush to free him in 2006.
Kurnaz also passed his remarks on the damning US Senate report issued last week, which revealed the use of torture by the CIA following the 9/11 terrorist attacks.
"There is nothing new in the report," Kurnaz said, adding that this was a game which has been played by intelligence services for many years.
"I do not think that the report would be beneficial," he said.
The report that caused an international outcry unravelled that the US Central Intelligence Agency (CIA) employed the use of nudity, waterboarding – which it said induces convulsions and vomiting -, sleep deprivation for as much as 180 hours, and unnecessary “rectal hydration.”