A riot broke out after a man entered an apartment in Skellefteå where a woman and another man were during the night towards Monday.
All three are now suspected of assault, or attempted crime.
The man who entered the apartment was hit in the head with a hammer, but received no serious injuries, according to the newspaper Norran, which was the first to report on the incident.
"The plaintiff has received several blows with a hammer to the head and he has been partially defenseless," prosecutor Andreas Nyberg told SVT.
The perpetrator was arrested today on probable cause on suspicion of aggravated assault.
He himself has claimed self-defense.
Suspected himself for crime
The victim himself is suspected of a crime.
He is suspected of attempted aggravated assault and was previously arrested.
The investigation against him continues.
The woman is also suspected of aggravated assault.
Everyone involved denies the crime.
Andreas Nyberg does not want to go into exactly what has happened, but a blood image analysis will be done to get a clearer picture of the process.
For example, via such an analysis, it should be possible to see where the persons were in the apartment during the course of events.