Clashes broke out near Brussels Central station on the margins of a protest organized by Belgium's socialist trade union against the federal government's austerity plans.
According to The Belgian Times, as thousands of demonstrators gathered at the station on Friday, a smaller group clashed with police and threw wooden beams, glass bottles and rubbish bins.
Police were deployed in large numbers around the stations, checking groups of young people not wearing the union's colors.
Police said the main union march passed off peacefully, but that "groups of troublemakers were responsible for serious incidents before and after the march."
Riot police responded to these demonstrators with tear gas, water cannons and baton charges. Police insisted that those "causing public order problems had no connection" to the march.
Reporting from Brussels, Al Jazeera correspondent Rosie Birchard said damage occurred during Friday morning's protests, with a "strong burning smell in the air" from fires that were set and from tear gas.
"Police and emergency services arrived, began to disperse or clear the area, then the protests flared up again. So it's still early in the day; often these kinds of incidents get worse in the evening in terms of the level of street violence," Birchard explained.
"Some young people turned up, they said they were inspired by what they had seen in France about school protests, and they also wanted to talk about the education environment they are studying in," she said, adding that students feel they are "not being listened to."
The clashes followed a tense week in the city of Liege when authorities banned gatherings as students clashed with police and vandalized shops. More than 200 people were arrested in Liege, and dozens of police officers were injured.
The ABVV and the Christian ACV, the country's two largest trade unions, held protests on Friday morning, with demonstrators marching from Brussels Central station to Brussels South station under the slogan "don't touch our money."
Police said around 30,000 people took part in the protests, while ABVV had earlier estimated attendance at 50,000.
The anger stems from the government's austerity measures, as officials consider a new budget in opposition to potential measures affecting purchasing power, wage indexation and value-added tax (VAT), as well as a plan to introduce annualized working hours.
Meanwhile, ACV held a separate protest with hundreds of activists at the headquarters of the governing coalition parties in the capital.
