Demonstrators took to the streets in the Swedish city of Eskilstuna Friday to show support for the Muslim community after an alleged Christmas Day arson attack on a local mosque. The AFP reported that several hundred people organized on Facebook and showed up at the damaged structure to “deliver a message of friendship,” as one police official reportedly put it.

The alleged attack sparked a fire that swept through the mosque and injured five people, one of them critically. One witness reportedly said a firebomb was thrown through a closed window in the mosque, which at the time had about 70 worshippers inside. In a separate, possibly related incident, windows in a second local mosque were also broken. So far no suspects have been identified.

The incidents are thought to be part of a wave of rising anti-immigrant sentiment in the traditionally tolerant Scandinavian nation. As the Spectator reported in September, Sweden’s far-right Democrats are now the third-largest political party in the country, having won much of their support through a tough anti-immigrant stance. And their popularity is still growing, with some polls showing their support as high as 16 percent, up from 12.9 percent in September, according to AFP.

Swedish officials were quick to condemn Thursday’s incidents, with the country’s culture minister, Alice Bah Kuhnke, calling them “a direct attack against religious freedom in our country” in an interview with Swedish Radio News, according to the New York Times. The suspected arson attack is the latest in a number of reported incidents against Swedish mosques over the last year. As the Times reported, black swastikas were painted on a Stockholm mosque in January.

On Friday, Swedish Radio News reported that local police could not confirm that Thursday’s mosque fire was the result of a deliberate attack. Although officials had told the station they were looking for a man who had thrown something through the mosque window, they now say that claim was made amid “chaos” and could not be substantiated.

Christopher Zara is a senior writer who covers media and culture. Got a news tip? Email me here. Follow me on Twitter @christopherzara.