Swiss authorities have arrested a suspect in connection with a shooting at a rave event in northern Switzerland that resulted in one fatality and multiple injuries. The 43-year-old Swiss national was detained shortly before 1 a.m. on Monday, according to a statement from police in Aargau canton, where the incident occurred.

The shooting took place during the early hours of Sunday in Aarau, the capital of Aargau. Law enforcement confirmed that a 22-year-old woman died at the scene from her wounds. Five other individuals—four men and one woman, aged between 24 and 27—sustained injuries ranging from minor to severe and were subsequently transported to hospitals for medical treatment.

Authorities indicated that the investigation is ongoing to determine the motive behind the attack. At present, police believe the incident involved a single perpetrator, although they have not disclosed further details about the circumstances surrounding the arrest or the suspect’s potential motivations.