A group of vandals attacked a Turkish mosque in southern Netherlands, local television channel RTV Rijnmond reported. The station said at least 15 people attacked the mosque with iron bars and shattered the windows. Two people were slightly injured during the attack on Thursday. It was unclear if the injured included worshippers.

The mosque is operated by the Netherlands' Turkish Federation. Vedat Özdal, a senior official with the association running the mosque, labeled the attack "cowardly" and urged the community to remain calm, saying it was the responsibility of the police and local municipality to find the attackers.

Piet Sleeking, the deputy mayor of Dordrecht, where the mosque is located, also called on the community to remain calm.

Witnesses who spoke to the television station said the attackers were linked to the PKK terrorist organization, though it was unclear how that was known.

The PKK is listed as a terrorist organization by Turkey, the U.S. and the EU. It has waged a violent campaign in southeastern Turkey since last summer and killed hundreds of Turkish security personnel and civilians in separate attacks during that time.

In 2014, another Turkish mosque, located in the eastern Dutch city of Enschede, was attacked with fireworks. Selimiye Mosque in Enschede was also victim to Islamophobic and racist attacks in the past, which included xenophobic graffiti and threat notes.

Like elsewhere in Europe where Islamophobia rises with the influx of Muslim refugees, mosques in the Netherlands are often target of the attacks. One-third of the mosques in the country have suffered from various forms of attack over the past decade according to research by Ineke van der Valk from the University of Amsterdam. Attacks are often confined to vandalism, arson attempts, threat letters or pig's heads thrown into mosques in a bid to anger Muslims who deem the animal as unclean. In 2015, 28 cases of attacks targeting mosques were recorded and this year, Muslim residents reported to Dutch authorities dozens of threat letters sent to mosques.