Shortly after 01 o'clock on Friday, the rescue service and police were alerted to a fire in a residential area on Scheelegatan in Köping.
Two garbage rooms were on fire and a car was on fire when the rescue service arrived at the scene.
No person was arrested after the incident.
No one should have been injured in connection with the fire.
Four cars are said to have been damaged in the fire and due to heat development, there were cracks in windows in nearby apartment buildings, according to the police.
A technical investigation will be carried out on site.
There have previously been about 15 fires in Köping since mid-June that the police suspect have been started.