Riots broke out in the southern Swedish town of Malmo on Friday after far-right activists engaged in anti-Islamic activities, police said.
The protestors set car tires on fire and threw objects at police officers.
About 300 people were on the streets of Malmo with violence escalating as the evening wore on, according to police and local media.
"We don`t have this under control but we are working actively to take control," a police spokesman said.
"We see a connection between what is happening now and what happened earlier today," he said.
The riots started right after Rasmus Paludan, leader of Danish far-right political party Hard Line, had been denied permission to have a meeting in Malmo and was stopped at the Swedish border, according to reports.
"We suspect that he was going to break the law in Sweden," Calle Persson, spokesman for the police in Malmo told AFP.
"There was also a risk that his behaviour... would pose a threat to society." he added.
Earlier in the day, far-right activists burned a copy of the Quran after Paludan was denied permission to hold a meeting there.
Paludan reportedly was cross after he was not given permission to enter the Swedish border.
Paludan last year burned a Koran wrapped in bacon -- a meat that is offensive for Muslims.
Paludan had been banned by the Swedish authorities for two years for anti-Islamic rhetoric.
Various anti-Islamic activities took place in Malmo on Friday. A newspaper named Daily Aftonbladet reported that three men were seen kicking a copy of the Quran between them in a public square.
