On Tuesday night, cars were torched in western and southern Stockholm, and stones were thrown at police officers and firefighters. One area affected, Rinkeby, saw similar rioting in 2010.
Kjell Lindgren of the Stockholm police told Aftonbladet newspaper that the unrest had spread from the original rioting in Husby.
“It feels like people are taking the opportunity in other areas because of the attention given to Husby,” he said.
Earlier on Tuesday, Prime Minister Reinfeldt said: “We’ve had two nights with great unrest, damage, and an intimidating atmosphere in Husby and there is a risk it will continue.
“We have groups of young men who think that that they can and should change society with violence. Let’s be clear: this is not okay. We cannot be ruled by violence.”
More than 80% of Husby’s 12,000 or so inhabitants are from an immigrant background, and most are from Turkey, the Middle East and Somalia.
Mr Reinfeldt said the situation in the district had been improving in recent years, with more jobs being created and a falling crime rate.
However, local people accused the police of racism.
Rami al-Khamisi, a law student and founder of the youth organisation Megafonen, told the Swedish edition of online newspaper The Local that he had been insulted racially by police. Teenagers, he said, had been called “monkeys”.
He said the crowd was reacting to a “growing marginalisation and segregation in Sweden over the past 10, 20 years” from both a class and a race perspective.
Dare we say Islamic influence?