Around 30,000 Kurdish supporters demonstrated in the German city of Frankfurt on Saturday against Turkish President Tayyip Erdogan and an April referendum that would give him sweeping new powers.
Protesters chanted "Erdogan terrorist" and "freedom for Ocalan", referring to Abdullah Ocalan, the jailed leader of the militant Kurdistan Workers Party (PKK), with many waving flags featuring Ocalan's face.
The PKK sympathizers also carried banned posters and flags even though the German Interior Ministry on March 2 updated its list of prohibited PKK symbols to include the image of the terrorist organization's jailed head Abdullah Öcalan.
This comes despite German authorities blocking nearly two dozen planned rallies by Turkish government ministers or politicians ahead of an April 16 referendum on constitutional changes in Turkey.
Germany outlawed the PKK in 1993 but the group is still active in the country, with more than 14,000 followers.
Germany, the European Union, NATO and the United States consider the PKK to be a terrorist group, along with the likes of ISIS and Al Qaeda, and the PKK is actually banned in Germany, but still German authorities allowed its supporters to stage an open and public rally in its support.
The protest brought swift condemnation from Turkey, which said Germany was allowing open support for terrorism.
The Kurdistan Workers' Party or PKK, launched an insurgency against the Turkish state in 1984. More than 40,000 people have been killed over 33 years of fighting between the two groups.
The PKK resumed its armed terrorist campaign against Turkey in July 2015 after ceasefire between itself and Turkey came to an end.
Since then, the PKK has been responsible for the deaths of approximately 1,200 Turkish security personnel and civilians, including women and children, while losing over 1,000 of its own militants.