"We are investigating a case of manslaughter and we have three people under arrest," police chief Oskar Öster told the local newspaper.
The police received the report around 4 a.m. on Midsummer's Eve and found a deceased person in central Strängnäs. Police technicians have reportedly cordoned off the scene.
The suspected crime is believed to have taken place both indoors and outdoors, and the three detainees, whose relationship to the deceased is still unclear, are between 30 and 50 years old.
