John Walker Lindh, also known as the “American Taliban,” is scheduled to be released from prison in May.

Lindh, who was captured in the initial phases of the Afghanistan War, was involved in a prisoner uprising that resulted in the death of CIA paramilitary officer Michael “Mike” Spann, the first American killed in the Global War on Terror.

At the time of his death, Spann was interrogating Taliban and al-Qaeda prisoners inside the Qala-i-Jangi fortress, near the town of Mazar-i Sharif. Spann was accompanied by another CIA officer and their Northern Alliance bodyguards. While the questioning was taking place in the fortress’ courtyard, some of the prisoners ran toward their guards and detonated hidden grenades. Soon, they found weapons, and a full-fledged firefight broke out. Spann was swarmed by dozens of terrorists and was killed. It took the Northern Alliance forces days and the support of Green Beret teams from the 5th Special Forces Group and British Special Boat Service (SBS) operators to quell the uprising.

Lindh, who has obtained Irish citizenship because of his maternal grandmother, plans to relocate to Ireland upon his release. “I don’t really know what to expect from the Irish government,” he said from his prison cell. “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 U.S. practically impossible.”

According to a profile article by ForeignPolicy.com, Lindh told “a television news producer that he would continue to spread violent extremist Islam upon his release.” At the time of his capture, Lindh was 20-years-old.

In an interview with Al.com, Johnny Spann, the father of CIA officer Michael Spann, said: “This is, of course, for the family disturbing news. We never thought 20 years was a long enough sentence. He’s as much responsible for Mike’s death as the people who beat him and shot him. He had a chance to say he was an American and save Mike’s life and other Americans’ lives. He did not do that. It’s no different than if he pulled the trigger.”

“He was a traitorous terrorist and supported terrorist groups,” Johnny Spann said of Lindh. “He’s sending out messages of support to those groups. He’s never renounced his affiliation with al-Qaeda,” he added.

Upon earning a degree in criminal justice from Auburn University, Mike Spann commissioned in the Marine Corps as an artillery officer and served for eight years. He then joined the CIA’s stealthy Special Activities Division (SAD) as a paramilitary officer in 1999.

In 2016, some 15 years after his death, the CIA honored Spann by adding a star with his name on the CIA Memorial Wall. The agency had released a statement at the time saying Spann’s “last act, just before he was killed by those who had supposedly surrendered, was to warn an agency colleague of the imminent danger.”