Police had to seal off parts of the centre of Brussels, deploy water cannons and fire tear gas to disperse crowds following violence during and after Morocco’s 2-0 upset win over Belgium at the World Cup.Dozens of rioters set steps on fire and pelted cars with bricks. Police moved in after one person suffered facial injuries, said Brussels police spokeswoman Ilse Van de Keere.Brussels mayor Philippe Close urged football fans to stay away from the city centre and said authorities were doing their utmost to keep order in the streets. Subway and tram traffic had to be interrupted on police orders.