Around 35,000 people took to the streets of Brussels on Sunday to protest against stricter coronavirus measures and in particular the coronavirus pass, according to police.
According to a report by the Belga news agency, participants threw fireworks at security forces. Police deployed water cannon and tear gas.
The demonstration was authorized by the city of Brussels, a spokesperson for the police told Belga. A march route ending at the Belgian capital's European quarter was planned in consultation with the police, she said.
The demonstrators are protesting the increasing necessity of showing a vaccine certificate in Belgium, for example, when going to eat at a restaurant.
The number of daily recorded coronavirus cases in Belgium has increased significantly in recent weeks, most recently, to an average of over 12,000 new infections per day in the country of about 11.5 million inhabitants.
Last Monday, over 20,000 new cases were recorded in a single day.
Between November 13 and 19 there was an average of 268.3 coronavirus-related hospital admissions per day according to official figures, an increase of 29 per cent on the previous week.