Four men were arrested after the fight, which broke out at 2am in the port town, 60 kilometres south of Stockholm.
Police were told that firearms may have been involved as a witness claimed to have heard shots being fired.
The first police unit at the scene called for back-up after some of the estimated 100 people involved in the fight urged a group of around twenty people to redirect their aggressions at the officers.
“We’ve classified it as rioting,” said police sergeant Birger Karlsson.
Four men in their twenties were arrested for rioting and are also suspected of assaulting security guards as well as making threats and acting violently towards the police officers.
None of the participants in the mass brawl sustained any serious injuries.
“There were a few minor injuries,” said Karlsson.
Police are hoping to able to ascertain a cause for the fighting once they begin questioning the four men who have been arrested.