A second person sustained minor injuries after being hit by the same car.
Around 15 people were involved in the fight in the centre of the town, 200 kilometres north-west of Stockholm.
Police arriving at the scene found the victim lying on the street after a car drove straight into the crowd at the height of the brawl.
“There was a fight between two gangs after a liquor deal got out of control,” said police spokesman Crister Nelefledt.
Police said two people have been arrested on suspicion of murder, with an alternative charge of manslaughter, while a third person is suspected of aggravated assault.