Clashes erupted in an immigrant neighborhood in Sweden’s third largest city after an anti-Muslim protester set fire to the Quran, police said Monday.

Police in Malmo said they were pelted with rocks and dozens of cars were set on fire, including in an underground garage, describing the events that started Sunday and lasted overnight as “a violent riot.”

The clashes started after an anti-Islam activist Salwan Momika on Sunday burned a copy of the Quran and an angry mob tried to stop him while police, some of them helmeted, detained several people. At least three people have been detained, police said.

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Early Monday, an angry crowd of mainly young people also set fire to tires and debris and some were seen throwing electric scooters, bicycles and barriers in Malmo's Rosengard neighborhood, which has seen similar clashes in the past. There were several banners relating to the Quran burning.

“I understand that a public gathering like this arouses strong emotions, but we cannot tolerate disturbances and violent expressions like those we saw on Sunday afternoon," senior police officer Petra Stenkula said.

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“It is extremely regrettable to once again see violence and vandalism at Rosengard,” she said.

In the past months, Momika, a refugee from Iraq, has desecrated the Quran in a series of anti-Islam protests mostly in Stockholm that have caused anger in many Muslim countries. Swedish police have allowed his actions, citing freedom of speech.

The Quran burnings have sparked angry protests in Muslim countries, attacks on Swedish diplomatic missions and threats from Islamic extremists. Muslim leaders in Sweden have called on the government to find ways to stop the Quran burnings.

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Sweden dropped its last blasphemy laws in the 1970s and the government has said it has no intention to reintroduce them.

However, the government has announced an inquiry into legal possibilities for enabling police to reject permits for demonstrations over national security concerns.