Germany did not learned its lesson from 9/11!

His sentence ended in March, but he remained in custody pending an extradition ruling.

On Tuesday, the superior state court in Duesseldorf ruled against extradition and ordered Kaplan’s immediate release.

The court said there were "serious grounds" to believe that, if extradited, Kaplan would be prosecuted using testimony "extorted by police" and that the trial would "have the character of political persecution."

Official documents from Turkey raised concern that Kaplan’s followers were tortured by Turkish police during investigations in 1998, it said.

The German government backed the extradition effort, which appeared to clear a major hurdle when Turkey abolished the death penalty last year. But Germany also sought Turkish assurances that Kaplan wouldn’t be tortured on his return.

Kaplan’s group calls for the overthrow of Turkey’s secular government and its replacement with an Islamic state.

Interior Minister Otto Schily has described the group as a "breeding ground" for terrorists, though he said it has no links to al-Qaida or other international terrorist groups.

Schily called Tuesday’s court decision "regrettable" and said Turkey had given assurances "that the principles of international law would be observed."

However, he noted that two further cases are pending against Kaplan — a deportation order from the city of Cologne and a government decision to revoke his entitlement to asylum in Germany, both of which Kaplan has appealed. Court proceedings were suspended while the Turkish extradition request was processed.

Kaplan took over Caliphate State from his father, Cemaleddin, who died in 1995. Cemaleddin fled Turkey after a 1980 military coup and founded the group in 1984 after gaining political refugee status in Germany with his family.