At 19 o'clock on Friday, the police blocked off the bus station in Karlskoga.
The police are silent about the incident but one person is taken to hospital.
- It has been cordoned off during the evening.
We work with investigative technical measures, interrogate witnesses and try to locate the perpetrator, says Olga Korpela at duty officer Polisregion Bergslagen.
At present, there is no suspected perpetrator.