The California man who became known as the American Taliban after his battlefield capture in Afghanistan in November 2001 is being released from prison.

Thirty-eight-year-old John Walker Lindh has spent more than 17 years in prison after pleading guilty to providing support to the Taliban.

His status in the inmate registry changed from scheduled for release on Thursday from the US federal prison in Terre Haute, Indiana, to “unknown”.

Officials later confirmed the release.

American Taliban Release
John Walker Lindh, pictured in 2002 (Sheriff’s Office/AP)

His lawyer in Virginia, Bill Cummings, said “no comment, bye-bye” when asked if Lindh had been freed.

Lindh’s plea deal called for a 20-year sentence, but he is getting out a few years early for good behaviour.

His release has been opposed by the family of Mike Spann, who was killed in Afghanistan during an uprising of Taliban prisoners.

Mr Spann had interrogated Lindh shortly before the attack.

A judge recently imposed additional restrictions on Lindh’s post-release supervision, including monitoring of his internet use.

US secretary of state Mike Pompeo said Lindh’s early release was “unexplainable and unconscionable”.