Stockholm police called in reinforcements from across Sweden to quell a possible sixth straight night of riots in the country's capital.
The nightly unrest led Britain's Foreign Office and the United States embassy on Friday to warn their nationals against travelling to the affected areas.
"We will be getting reinforcements from Gothenburg and Malmoe tonight," police spokesman Kjell Lindgren said, naming the country's next two largest cities.
Parents and volunteer organisations who have patrolled the streets in recent nights have helped decrease the intensity of the unrest, Lindgren said.
No information about the specific number of police due to arrive was revealed.
Minister for Integration Erik Ullenhag said the violence was being committed by a small group of people, many of whom were already known to the police and did not live in the area were they were causing trouble.
"What we are seeing are extreme, unusual events. But we need to be absolutely clear about one thing: we can never accept violence," the minister said.
"Violence has a negative impact on social segregation. We know there is discrimination based on where people live, and these events do not improve the image of these residential areas, where there are plenty of positive things going on too.
"At the end of the day, what this is all about is that we must create a positive belief in the future in areas at risk."
The fifth night of violence on Thursday resulted in 30 cars being torched and a primary school being set ablaze in Kista, an area that is known as Sweden's IT hub.
The 94 students will move into improvised classrooms in nearby office buildings from Monday.
"Five nights in a row - it's incomprehensible," said Faisal Lugh, whose two children are pupils at the school.
"My children asked about the things they had there: 'How about my books? My rain jacket? My pictures? Are they all
gone?'" said Lugh, who works for an unemployment office and often helps new immigrants find jobs.
Eight people, mostly in their early 20s, were arrested during the night. Youth unemployment is especially high in immigrant neighbourhoods like the ones where the riots have taken place.
The trouble began in the suburb of Husby, where 80 percent of inhabitants are immigrants, triggered by the fatal police shooting of a 69-year-old Portuguese immigrant last week after the man wielded a large knife in public.
The unrest has also sparked a debate among Swedes over the integration of immigrants, many of whom arrived under the country's generous asylum policies, and who now make up about 15 percent of the population.
A fault-line has been exposed between a well-off majority and a minority, often young people with immigrant backgrounds, who are poorly educated, cannot find work and feel pushed to the edge of society.
Due to its liberal immigration policy, Sweden has in recent decades become one of Europe's top destinations for immigrants, both in absolute numbers and relative to its size.
Many of those who have arrived struggle to learn the language and find employment, despite numerous government programmes.