Eleven people remained in police custody on Sunday after violence broke out around the Louise shopping district of Brussels on Saturday afternoon.

A police officer suffered a fractured skull after receiving a projectile to the head. He remains in hospital and is not in a critical condition. The Brussels public prosecutor said 71 arrests were made - 60 were administrative arrests and the other 11 suspects face prosecution.

The incidents occurred around Avenue Louise, Porte de Namur and Chaussée d'Ixelles on the sidelines of an otherwise peaceful demonstration against slavery on Place Poelaert.

Some witnesses reported taking shelter inside Inno department store as young people began smashing shop windows and vandalising cars in the street outside. Riot police were called in and calm returned to the neighbourhood around 20.00 in the evening.

Brussels' Regional Security Council will meet on Tuesday to discuss the incident. The Brussels-City Ixelles police force is appealing for any smartphone footage from witnesses which could help identify the perpretrators. Any images can be sent to zpz.polbru.info@police.belgium.eu

Brussels mayor Philippe Close condemned the "unacceptable behaviour of a handful of individuals who have spoiled a demonstration against slavery".

Interior minister Jan Jambon said "troublemakers have once again behaved in an unacceptable way", calling for "zero tolerance for young people who destroy other people's property".

Foreign affairs minister Didier Reynders added: "The people of Brussels are fed up with violence. These people are destroying businesses,

destroying property."