An American Taliban fighter who will be freed from prison after 17 years behind bars has reportedly refused to renounce terrorism and still supports the extremist group.

John Walker Lindh, 38, will be released from prison in May, but officials say that the California native is still holding onto the same beliefs he had in 2002.

Lindh was among a group of Taliban fighters who were captured by US forces in November 2001, just months after the September 11 attacks and the beginning of the war in Afghanistan.

Hours later, 500 people were killed after Lindh's fellow prisoners staged an uprising and killed a CIA operations officer.

Former American Taliban fighter John Walker Lindh (pictured in 2002) has refused to renounce terrorism and still supports the extremist group. He will be released from prison in May

Lindh, who was 20 years old at the time, was one of only 86 people who survived the revolt.

He was named 'Detainee 001 in the war of terror' and, in 2002, was convicted of supporting the Taliban and sentenced to 20 years in prison.

He is scheduled to be released in May after serving 17 years behind bars

Lindh (pictured in an undated police photo) has spent the last 17 years behind bars

In 2016, the National Counterterrorism Center found that Lindh was continuing to 'advocate for global jihad', according to documents obtained by Foreign Policy.

He was also continuing to 'write and translate violent extremist texts', it added.

The document also claims that in 2015 Lindh told a television news producer 'that he would continue to spread violent extremist Islam upon his release'.

During his sentence, Lindh filed two suits against the Bureau of Prisons so that he could continue practicing the tenets of Islam.

In 2013, Lindh won the right for communal prayer. The following year, he argued that he should be allowed to wear his pants above the ankle.

Lindh went to the Middle East in 1998. He dropped out of high school at 17 and went to Yemen to learn Arabic with the support of his parents.

Lindh was among a group of Taliban fighters who were captured by US forces in November 2001, just months after the September 11 attacks and the beginning of the war in Afghanistan. He is pictured here bein led to a prison by a Northern Alliance soldier following his capture

Hours later, 500 people were killed after Lindh's fellow prisoners staged an uprising and killed a CIA operations officer. He is pictured here being treated in a hospital after his capture

Lindh (pictured after his capture during a television interview) was named 'Detainee 001 in the war of terror' and, in 2002, was convicted of supporting the Taliban and sentenced to 20 years in prison

He then went to Pakistan and joined forces with a group that was fighting to help Kashmir gain independence from India.

Lindh then arrived in Afghanistan and spent seven weeks at a training camp to prepare Taliban fighters. Al Qaeda volunteers also attended the camp to undergo training for terrorist attacks.

It was there that Lindh met Osama bin Laden, who thanked him for his participation in the group, he later told FBI investigators during his interrogation.

Lindh's parents, who had lost touch with him after he went to Afghanistan, only discovered where he was after CNN interviewed him following his capture.

Lindh (pictured in an undated family photo) went to the Middle East in 1998. He dropped out of school at 17 and heading to Yemen to learn Arabic

A picture of Lindh seen on a facsimile of his passport at the Arabia Hassani Kalan Surani Bannu madrassa (Islamic school) in Bannu, Pakistan in 2002

It was in prison that Lindh applied for Irish citizenship, and he has since confirmed that he plans to move there following his release.

When he was applying for citizenship, Lindh said he would explain to the Irish government how his 'unique circumstances' would make 'survival in the US practically impossible'.

'Essentially I am seeking asylum from one country where I am a citizen in another country where I am also a citizen,' he told the London advocacy-group CAGE.

Ireland's government has already said that Lindh would not be refused entry to the state.