The police were alerted to the scene at 19:00 on Wednesday evening.
We have an extensive ongoing search effort after one or more perpetrators and are holding interviews with witnesses, says the police's press spokesperson Mats Eriksson.
No one is reported to have been injured in connection with the incident.
We have now blocked off the residence and have technicians on their way for an investigation.
No suspected perpetrator has been arrested but several people have been taken in for questioning, according to the police.
The incident is being investigated as an attempted murder, as well as a serious offense against the weapons law.
