John Walker Lindh, a former American Taliban militant convicted in 2002 for supporting the terrorist organization and due to be freed in May, has obtained Irish citizenship in 2013 thanks to his family’s ancestry -- and he plans to live in the country when he leaves lockup.

The former Islamist fighter, named “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, along with a group of Taliban fighters who were captured by U.S. forces.

John Walker Lindh, a former American Taliban militant convicted in 2002 for supporting the terrorist organization and is due to be freed in May has obtained Irish citizenship in 2013 thanks to his family’s ancestry.

John Walker Lindh, a former American Taliban militant convicted in 2002 for supporting the terrorist organization and is due to be freed in May has obtained Irish citizenship in 2013 thanks to his family’s ancestry. (AP/Reuters)

Walker Lindh’s release has prompted security concerns, as he's expressed wishes to travel to Ireland while also not denouncing radical Islamic ideology, including allegedly making pro-ISIS comments to journalists.

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Moving to Ireland became an option for Walker Lindh after he obtained citizenship there, while still in prison, sometime in 2013 thanks to his family’s lineage.

His paternal grandmother, Kathleen Maguire, was an Irish citizen born in 1929 in a northwestern Irish town, the Foreign Policy magazine reported.

The Irish citizenship law allows for anyone, within certain restrictions, to ask for citizenship if at least one of their grandparents was an Irish citizen born in Ireland.

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Some previous reports indicated Frank Lindh, the convicted terrorist’s father, also holds Irish citizenship and urged his son to leave for Ireland after his release.

The National Counterterrorism Center penned a document dated Jan. 24, 2017 claiming Walker Lindh 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 document said.

But despite that, the Irish government won’t follow the example of the British government -- which rescinded a Jihadi bride’s British citizenship -- and won’t stop Walker Lindh from entering the country.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