The 45-year-old Turkish national, identified as Abdullah S., was "strongly suspected" of PKK involvement and operated a German regional cell under the code name "Hamza" in 2003 and 2004, federal prosecutors said in a statement.

He is also accused of taking orders from the Kurdistan Workers' Party (PKK) in the north of Iraq and managing the European wing's financial affairs.

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.