A 25-year-old man was injured and taken to Sahlgrenska hospital. He has minor injuries.
According to the police, the people involved are a group of far-right extremists and their left-wing opposites, the Afa (Anti-Fascist Action group).
Shortly before 6am on Friday morning, police were notified that a fight had broken out, with participants using iron pipes as weapons.
The police do not know exactly how many people were involved, but nine people have been taken in for questioning.
According to police spokesperson Cecilia Ekbladh, there is not much to be said until police have questioned all nine.
Speaking to TT, police spokesperson Ekbladh explained that the crime classification of grievous bodily harm could still change.
“So much is unclear until we have questioned everybody”.