A close relative found the men and alerted police at 9:26 pm on Sunday evening.
"We found that there were two dead people in the apartment and launched a preliminary investigation into murder in two cases," said Jonas Eronen, spokesman for the police in the Mitt region.
The apartment was in order, there were no signs of violence.
On Monday morning, police technicians arrived at the apartment to investigate the scene. Later, the bodies will be examined by forensic doctors.
- It is still unclear how the people died.
The suspected murders have occurred in the eastern parts of Västerås.
Police cite the incident as a suspected murder in two cases.
The text is updated.