Police have detained 40 German activists after scuffles with protesters during demonstrations outside a European Union summit.
Brussels Mayor Mr Freddy Thielemans, who oversaw the security operation, said about 12,000 protesters, including anti-globalists, took part in the demonstration.
Mr Thielemans said police arrested the 40 protesters, dressed in black and wearing balaclavas, after they were seen smashing four different banks and a police station.
He said they fired wooden and steel projectiles with slingshots at riot police, injuring two, and also damaged several vehicles.
"We only apprehended those carrying sticks, stones and steel pellets," Mr Thielemans said.
Police used water cannons against protesters after several, believed to be among the 40 taken into custody, started fires on the street, Brussels city police Commissioner Mr Christian De Coninck said.
The 40 were to remain in jail overnight while authorities decided whether to press charges, Mr De Coninck said.
PA