A person was found injured in a stairwell in an apartment building, after the police were alerted to an apartment outside Norrköping in connection with a suspected riot, the police write on their website.
The alarm came just after 9 pm on Wednesday night
The person on the stairs had a wound on his upper body which the police believe may have been caused by a sharp concussion, and was taken to hospital by ambulance, awake and talkable.
Another injured person was found inside the home, who, however, was not in need of ambulance care.
Both people have been arrested on suspicion of attempted murder and assault.
The home has been cordoned off for technical investigation and the police have questioned witnesses.