Three people are in hospital in Rotterdam after they were seriously injured when Dutch police fired shots during a violent protest against COVID-19 measures.
Crowds of several hundred rioters torched cars, set off fireworks and threw rocks at police during the protests on Friday evening. Police responded with warning shots and water canons.
Rotterdam police posted on Twitter on Saturday that 51 people had been arrested, half of whom were under 18.
"Four rioters where wounded when they were hit by bullets, they remain in hospital," police added, in an update after earlier reporting two wounded.
Authorities are investigating the shootings including looking at the question if the injured people where hit with police bullets, they added
The city's mayor, Ahmed Aboutaleb, said the protest had turned into "an orgy of violence".
"Police were forced to draw their weapons and even fire direct shots," he told a press conference early on Saturday.
Dutch justice minister Ferd Grapperhaus said in a statement the "extreme violence" against police and fire fighters in Rotterdam was "repulsive".
"The right to protest is very important in our society but what we saw last night was simply criminal behaviour," Grapperhaus said.
Protesters had gathered to voice opposition to government plans to restrict access to indoor venues to people who have a "corona pass", showing they have been vaccinated or have already recovered from an infection.
The pass is also available to people who have not been vaccinated, but have proof of a negative test.
Organisers of a planned protest Saturday in Amsterdam against the measures said they had cancelled the event after Friday's violence.
Even so, several thousand protesters showed up for a march around the city's central Dam square. The march remained peaceful, monitored by a heavy police presence.
Later on Saturday several hundred protesters who stayed behind gathered at the Museumplein, a tourism hotspot, also closely watched by riot police present.
In the southern city of Breda, a musical protest called by local DJs against current measures, which include the 8pm closure of bars, restaurants and clubs, attracted a few hundred people.
The Netherlands reimposed some lockdown measures last weekend for an initial three weeks in an effort to slow a resurgence of contagion, but daily infections have remained at their highest levels since the start of the pandemic.
Australian Associated Press
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