The police were quickly in place and were able to arrest a suspected offender at the age of 45. The elderly man was taken to hospital by ambulance, but it is unclear how serious injuries he received.
Forensic technicians will conduct a closer investigation of the crime scene and the incident is initially classified as attempted murder.
The police do not yet have a clear picture of what caused the abuse.
- This is being investigated in this now, says Peter Kjellkvist, press spokesman at the police's command center.