A woman in her 20s was beaten with a machete and had to be taken to hospital by ambulance.
The assault is described as serious, but according to the police's spokesperson Daniel Wikdahl, she is not seriously injured.
- There are between 15 and 20 people who had a party in a home in Västerås.
Since then, disagreements have arisen with some outsiders, which led to the young woman being beaten.
As a result, more fights broke out, he says.
Another two men in their 20s and a woman in her late teens were beaten, but they did not have to seek medical attention.
- No arrests have been made. The perpetrators are unknown to us and had deviated from the place before we got there, says Daniel Wikdahl.