John Walker Lindh, a former American Taliban militant convicted in 2002 for supporting the terrorist organization, is due to be freed in May.

The former Islamist fighter, dubbed “Detainee 001 in the war on terror,” was arrested in 2001, just months after the Sept. 11 attacks and the start of the war in Afghanistan. Then just 20 years old, he was among a group of Taliban fighters who were captured by U.S. forces.

Within a year, Walker Lindh was convicted of supporting the Taliban and sentenced to 20 years in prison -- even as some hardliners urged authorities to consider treason charges that could have resulted in the death penalty.

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Walker Lindh’s release later this year is likely to be met with headaches for security services across the globe, especially since he has since acquired Irish citizenship and plans to move there -- even though he hasn’t denounced radical Islamic ideology and has even made pro-Isis comments to the media.

The National Counterterrorism Center penned a document dated Jan. 24, 2017 claiming the former Taliban fighter remains as radicalized now as he was in 2001.

“As of May 2016, John Walker Lindh (USPER) — who is scheduled to be released in May 2019 after being convicted of supporting the Taliban — continued to advocate for global jihad and to write and translate violent extremist texts,” the Foreign Policy magazine reported.

The report added Walker Lindh told “a television news producer that he would continue to spread violent extremist Islam upon his release.”

It appears, however, that the Irish government won’t follow the example of the British government -- which rescinded a Jihadi bride’s British citizenship -- and won’t stop Walker Lindh from entering the country.

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“Irish citizens are not subject to immigration control,” the spokesman for Ireland’s Department of Justice told the London Times. “Therefore, if a person has Irish citizenship and presents their Irish passport on arrival, they will not be refused entry to the state.”

Walker Lindh confirmed his plans to head to Ireland after his release in remarks he made to CAGE, a London-based organization focused on supporting people impacted by the War on Terror.

“I don’t really know what to expect from the Irish government. I know virtually nothing about them. I think the only reasonable way to present my case to them is to explain my unique circumstances that make my survival in the US practically impossible. — John Walker Lindh

“I don’t really know what to expect from the Irish government,” he wrote to the group, according to the newspaper. “I know virtually nothing about them. I think the only reasonable way to present my case to them is to explain my unique circumstances that make my survival in the US practically impossible."

He added: “Essentially I am seeking asylum from one country where I am a citizen in another country where I am also a citizen. The worst they can do is decline my request. I figure it is worth at least trying.”

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In the U.S., meanwhile, multiple lawmakers have called for the creation of a registry of convicted terrorists, modeled after sex-offender registries, as multiple high-profile releases are set to take place in the next two years.

The Associated Press contributed to this report.