A man has been arrested on suspicion of attempted murder in Östersund, according to the police.
An injured person has been taken to hospital by ambulance.
It is unclear how badly injured the person is and the police do not want to comment on the type of injuries involved.
An alarm about the injured person came in to the police at 10 pm on Tuesday.
The crime scene has been cordoned off pending a technical examination and the police are conducting interviews.