Riot police backed by water cannon vehicles were called to the Place de la Bourse-Beursplein in the center of the Belgian capital, Brussels, on Sunday to keep right-wing groups away from demonstrators wanting to show solidarity following the deadly attacks on Tuesday.

Black-clad protesters shouting slogans against immigrants and the jihadist "Islamic State" group faced off with police in front of the city's stock exchange building, where a group of other demonstrators had gathered to mourn the victims of the attacks.

Police used the water cannon to disperse the some 450 right-wing protesters. Some 10 people were detained.

DW's Dana Regev was at the scene.

Authorities had originally asked for no demonstrations to take place in Brussels over Easter, and a march organized for Sunday was postponed by the organizers in response to the plea. Police officials feared that such gatherings could put the police force under too much strain, with resources vitally needed elsewhere to investigate the attacks.

More arrests

The protests and demonstrations came as Belgian prosecutors announced that police had carried out "terrorism-related" raids in Brussels and the northern cities of Mechelen and Duffel.

The federal prosecutor's office did not say whether the raids had anything to do with the attacks in Brussels, in which 31 people were killed and 270 wounded in bombings at the airport and in a subway station.

It said four new suspects were arrested, while five others were released after questioning.

The attacks on Tuesday were claimed by the jihadist group "Islamic State."

Security deficiencies

Also on Sunday, Belgian Interior Minister Jan Jambon acknowledged that security services in the country had been neglected over the past decades, leaving them ill-equipped to cope with the challenges posed by extremist violence.

But he said the government had invested 600 million euros ($670 million) in security over the past two years, adding, however, that it would take some time for the investment to show results.

Belgian authorities have faced accusations since the attacks of not having done more to prevent the tragedy.