German prosecutors say they have indicted a 25-year-old Islamic extremist on charges of being a member of two terrorist organizations fighting in Syria.

Federal prosecutors say German citizen Shahid Ilgar Oclu S., whose last name wasn't provided due to privacy rules, traveled to Syria in the fall of 2013 and joined the group Junud al-Sham.

In a statement Thursday, prosecutors said he "underwent weapons training and learned to use a firearm" but left the group after a few weeks "disappointed about the lack of combat missions." They say the suspect then joined the Islamic State group. He returned to Germany via Turkey on Dec. 23, 2013.

The man was arrested March 7 by police in the western city of Cologne.