The Netherlands' first night of curfew aimed at slowing coronavirus infections was met with widespread protests and rioting, police said on Sunday.
Spates of violence were reported from a total of ten cities, police said late Sunday.
Hundreds of protesters gathered in Amsterdam and Eindhoven on Sunday, pelting police officers with stones and fireworks despite a ban on gatherings.
Security forces hit back using water cannon in both cities as well as batons, horses and dogs. In Eindhoven police also used tear gas.
More than 30 people were detained, police said.
Dozens of people already protested the curfew late on Saturday night as it came into effect, hurling stones and fireworks at police officers and damaging squad cars in the small town of Urk north of Amsterdam, police said.
A group of youths also set fire to a coronavirus testing centre in the town and used pepper spray on a team of reporters from broadcaster NOS. Two people were detained and dozens of fines were imposed, according to police.
Among the other cities which saw violence are Venlo, Enschede und Roermond.
Nationwide, more than 3,600 fines were imposed and 25 people detained on the first night of the curfew.
There were also clashes with police in the southern town of Stein when officers tried to break up an illegal party attended by around 100 people.
The curfew, the Netherlands' first since the start of the pandemic, began on Saturday night and requires citizens to stay in their homes from 9 pm to 4:30 am. Violations of the curfew are being met with a 95-euro (116-dollar) fine.