A massive protest called by far-right groups to demand stricter asylum policies turned violent in the Hague, Netherlands, this Saturday.

According to local media, at least 30 people were arrested out of the approximately 1,500 people who attended the demonstrations. The protests saw clashes with the local police, as well as a police car set on fire. The Hague’s mayor called the protest “unprecedented” and “unworthy of the Netherlands.”

The headquarters of center-left political party D66 were also attacked. Party leader Rob Jetten condemned the violence, stating that populist uprising forces cannot gain the country’s support and that the demonstrations had “nothing to do with the Netherlands.”

Geert Wilders, chairman of the far-right Party of Freedom and an important figure in the Dutch anti-immigration scene, responded to Jetten, labeling his comments as “selective indignation,” further stating that there was no such political reaction during a recent clash between Turkish and Moroccan gangs in Beverwijk, or other instances of violence in the country.

Frans Timmermans, former EU Commissioner and current leader of the Labor Party in the Netherlands’ House of Representatives, said a debate is needed in order to draw the line concerning political violence in the country.

Prime Minister Dick Schoof further commented on the matter, describing the behaviour as shameless and unacceptable as well as calling for the country’s prosecution service to undertake all possible measures to hold the perpetrators accountable.