High school-age youths had also arrived from nearby municipalities, attracted by the brawl, but the police were there after receiving a tip-off.
On Monday evening, an unusually large number of young people began to stream into the area around the Hollola Municipal Centre.
The rumour of an impending mass brawl had spread quickly, and according to the police, there were high school-age youths from a wide area in Päijät-Häme, as far as Orimattila.
However, the police had been tipped off in advance of the planned clash and were quickly and visibly on the scene to calm the atmosphere.
After the authorities left for a while, the gathering started again, but the crowd broke up when the police returned.
The police recovered bladed and percussion weapons not only from the possession of the young people, but also from those abandoned at the scene.
The follow-up measures are aimed at least at interviewing the young people caught for possession of edged weapons.
Etelä-Suomen Sanomat first reported the gang fight.