Dutch police arrested about 400 protesters and used a water cannon Sunday after violence erupted around a demonstration in The Hague against measures put in place by the government to rein in the spread of the coronavirus.

A peaceful protest turned violent when dozens of what police said were soccer fans arrived and clashed with riot police near the city's central railway station.

Police used officers on horseback and a water cannon to disperse the crowd after police had been pelted with rocks and smoke bombs. There were no immediate reports of injuries.

It was unclear exactly how many people gathered Sunday at the demonstration that was initially banned by The Hague's mayor last week. On Sunday, the mayor gave permission for a brief protest, because fewer people attended than had been predicted last week.

Police tweeted in the evening that about 400 people were arrested throughout the day and that many had been released.

The Hague municipality said in a statement that the soccer fans and other groups had descended on the city from around the Netherlands.

"This has nothing to do with demonstrating or freedom of expression," Mayor Johan Remkes said in a statement. "This group deliberately aimed to disturb public order."

The protesters argue that a proposed law formalizing the coronavirus measures goes too far and is unconstitutional.

"I'm 60-years-old, and this is the first time I've ever demonstrated, but democracy is in danger" said Wouter Thijs, one of the protesters.

By the end of the afternoon, police had encircled dozens of protesters who refused to leave the Malieveld park. An officer with a bull horn informed them they were all arrested for breaching a law governing public demonstrations. They protesters were then led onto buses and driven away.

Police said they also arrested five people near the train station for throwing rocks.

The official outbreak death toll in the Netherlands is 6,090, though the true toll is higher because not everybody who died of suspected COVID-19 was tested. The country’s public health institute reported just one new death Sunday.