BERLIN (AP) — About 20,000 protesters demonstrated Saturday in the western German city of Cologne against the government of Turkish President Recep Tayyip Erdogan.

The rally in an industrial area along the Rhine River brought together pro-Kurdish demonstrators and members of the Alevi religious minority protesting Erdogan’s crackdown after a failed coup attempt in Turkey this summer.

Pro-Kurds meet on the banks of the Rhine / AP Photo/Martin Meissner

A group of about 200 to 300 Kurdish youth broke away from the main protest and several were taken into custody after throwing stones and bottles at police, authorities said. One police officer was slightly injured.

Police say many of the youth were wearing masks, and some were displaying banned symbols of the Kurdistan Workers’ Party, or PKK.

Pro-Kurdish demonstrators protest against Turkish president Recep Tayyip Erdogan and the political repression that followed July’s failed military coup, in Cologne, Germany Saturday, Nov. 12, 2016 / AP Photo/Martin Meissner

Erdogan’s government recently ordered the arrest of nine lawmakers of the pro-Kurdish HDP party, which it accuses of acting as the political wing of the outlawed PKK — an allegation the HDP rejects.

The PKK has waged a three-decades-long insurgency against the state, and Erdogan has blamed countries in Europe for supporting and arming the group.