A man who was detained for 13 years in the US prison camp at Guantanamo Bay, Cuba, was arrested partly in a case of “mistaken identity”, US officials admitted on Tuesday, said a report published on The Guardian.

During a hearing at the prison, officials conceded that Mustafa al-Aziz al-Shamiri, 37, was an insignificant foot soldier and not an al-Qaeda courier and trainer as they had previously believed.

A profile published by the Department of Defense maintains he fought in Afghanistan and mixed with members of al-Qaeda. However, officials concede that they wrongly believed he had a more significant role because he was “confused with others” with a similar name.

The Yemeni detainee appeared before a panel assessing whether he can be released, accompanied by a linguist and two personal representatives.

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“Mustafa Abd-al-Qawi Abd-al-Aziz al-Shamiri (YM-434) fought in several militant theaters and associated with al-Qaeda members in Afghanistan,” the unclassified detainee profile said.

“It was previously assessed that YM-434 also was an al-Qaeda facilitator or courier, as well as a trainer, but we now judge that these activities were carried out by other known extremists with names or aliases similar to YM-434’s.”

He has been an indefinite detainee after he was captured at Mazar-e-Sharif in Afghanistan and considered “too dangerous to release” but without adequate evidence to bring to trial.

Also read: Guantanamo inmate claims he was forced to have sex with female interrogators

A statement from al-Shamiri’s personal representative described him as “very cooperative, enthusiastic and supportive”, in the preparation for the board hearing.

“From the onset, he has demonstrated a consistent positive attitude towards life after Gitmo,” he said.

The representative’s statement added: “Mustafa does have remorse for choosing the wrong path early in life. He has vocalized to us that while he cannot change the past, he would definitely have chosen a different path. He wants to make a life for himself. He is aware that Yemen is not an option and he is willing to go to any country that will accept him.”

The 17-minute opening of the hearing was broadcast via video link to journalists in Arlington, Virginia.

They were then required to leave before classified details were discussed.

Al-Shamiri, who has been held as an enemy combatant without charge at the US prison camp since 2002, is one of 107 prisoners, 48 of whom have been cleared for release.

It is not certain when he will be cleared for release.

White House rejects Pentagon plan to close Guantanamo

The Obama administration has rejected as “too expensive” a Department of Defense cost estimate for closing the prison at Guantanamo Bay, Cuba, and building a replacement, and it has asked for revisions, the Wall Street Journal reported on Tuesday, citing officials familiar with the plan.

Also read: Pentagon to unveil Guantanamo closure plan

The Pentagon’s estimate for closing the prison and building another one in the United States was as high as $600 million, including $350 million in construction costs, the newspaper cited the officials as saying.