Sweden is largely seen as quiet and tranquil country, but that image was shattered recently as more than 100 cars were set ablaze in what police believe were coordinated attacks by groups of young men.

According to The New York Times, the string of attacks began on Monday night in a suburb of Gothenburg. A police spokesperson told the paper, 33 cars were set ablaze and another 50 or so more were damaged in the initial attack.

Shortly thereafter, there were arson attacks on vehicles in the Hjallbo district as well as the Kronogarden district of Trollhättan. Given the number of fires and the distances between them, police believe the attacks were coordinated using social media.

Police are continuing to investigate, but they’ve already made some progress as at least three people have been arrested. Among those taken into custody are a 16- and 21-year old as well as another man who was arrested after fleeing to Turkey.

There could be many more people involved as one witness told the paper she was in her apartment when she heard shouting and what sounded like firecrackers outside. She looked out her balcony and saw six to eight people, covered in black clothing, throwing Molotov cocktails into cars in the parking lot. A scene similar to this can be seen in the videos below.

The groups appeared to be even more violent in some areas as the BBC says a number of youths threw stones at police after they arrived on the scene to investigate the fires.

Sweden has seen widespread outbursts of arson in the past and there is little doubt the latest incident will play a role in elections next month.