A former top member of the leftist Red Army Faction terrorist group can be released from prison in January after having served the minimum 26 years of a life sentence for multiple murders, a German court ruled Monday.

The Red Army Faction, which emerged from German student protests against the Vietnam War, killed 34 people before disbanding in 1998. It subscribed to Marxist-Leninist ideology and sought to overthrow the capitalist West German government and fight perceived U.S. imperialism.

The Stuttgart state court ruled that it found no grounds for Christian Klar, 56, to remain behind bars any longer, spokeswoman Josefine Koeblitz said. After his Jan. 3 release he will remain on probation for five years, the court ruled.

The judges found "no evidence of a continued threat," Koeblitz said.

The court noted that Klar had shown himself "completely changed," urging against armed struggle.

Klar was convicted of involvement in nine murders, including those of federal prosecutor Siegfried Buback, industrialist Hanns-Martin Schreyer and Dresdner Bank chief Juergen Ponto — all in 1977, when the movement was at its peak.

He was sentenced to six concurrent life sentences, as well as individual 15-year, 14-year and 12-year sentences.

Before the ruling, Buback's son Michael called on Klar to divulge all the details of the killing, including who fired the fatal shots.