Police in Sweden's third-largest city say a recent surge in car fires could be linked to a crackdown on organized crime.

About 30 cars have been set ablaze in the southern city of Malmo since Friday, when police arrested three men accused of suspected gangland attacks involving guns and explosives.

No injuries have been reported but the fires tie up police and rescue officials and frighten residents.

Police spokesman Lars Forstell said Tuesday the fires were likely set in response to the arrests by "individuals who want to put us at work, so that we don't focus on what they're up to."

Four people were arrested late Monday for vandalism.

Malmo firefighters say there have been about 200 car fires this year, up from 150 in all of 2015.