The federal prosecutors said in a statement they indicted the 46-year-old, named only as Ali Ihsan K., on charges of "belonging to the foreign terrorist organisation Kurdistan Workers Party (PKK)".

The PKK, listed as a terrorist organisation by Turkey and by much of the international community, took up arms in Kurdish-majority southeastern Turkey in 1984, sparking a conflict that has claimed some 45,000 lives.

K., who was arrested in October last year and has since been held in custody, is suspected of acting as the top recruitment agent in northern Germany from May 2007 to September 2008.

"He was mainly responsible for collecting donations and contributions for the PKK in his region," the prosecutors said.

"In addition, he was in charge of making sure that enough PKK members from his area of responsibility attended events and demonstrations organised by the group," they added.

They said the suspect travelled to PKK "guerrilla units" in April 2008 where he stayed until September of that year.