The woman was arrested on Monday, the prosecutor's office announced in a press release.
The man was found seriously injured on Monday morning and died from his injuries. At the scene, the police arrested a person suspected of murder, who has now been arrested.
"Technical investigations are now being conducted and further questioning of the suspect," says Chief Prosecutor Hans Ihrman, who is leading the preliminary investigation.
At the latest by Thursday at 12 o'clock, the prosecutor will decide whether to request that the suspect be detained or to revoke the arrest decision.