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 soccer fans to stay away from the city center and said authorities were doing their utmost to keep order in the streets. Even subway and tram traffic had to be interrupted on police orders.

Morocco’s victory was a major upset at the World Cup and was enthusiastically celebrated by fans with Moroccan immigrant roots in many Belgian cities.

Belgium, ranked No. 2 in the world behind Brazil, had won its last seven group games at the World Cup before the upset. It was Morocco’s first win at a World Cup since 1998 (beating Scotland 3-0) and only its third ever.