Nearly 300 people were arrested in Paris after far-right groups clashed with riot police at a protest against gay marriage.
Stockholm has seen three nights of violence across the city following the shooting of a man by police last week.
Protests by teenage school students over sexual rumours about young teenage girls spread on photo-sharing service Instagram have turned violent after police intervened.
The Tanzanian archipelago of Zanzibar has experienced three anti-government protests so far this year; the latest, in mid-October, saw one police officer killed, roads blocked and shops closed across the capital, Zanzibar City.
In the years following the riots in the Paris in 2005, which began after the deaths of two French teenagers of North African descent were killed by electrocution whilst running from police in an electricity substation – the simmering crisis in the suburbs has slipped from the public’s mind, but the situation has not changed.