Homicide detectives have now been called in after a couple was found dead in a home in Lake Bonavista.
Police say the couple's adult son called for help Saturday afternoon after finding his parents, both in their early 60s, in the home.
When police arrived, one of the individuals was dead while the other was in medical distress and died a short time later.
Initial reports suggested carbon monoxide might have been a factor but emergency crews did not detect any levels of the gas in the home.
As well, the couple's pets were still alive. At this point, there is no obvious cause of death.
"Right now, the death is treated as suspicious," said Sgt. Thor Bahl with the Calgary Police Service. "I can tell you at this point we are waiting for results to come back from the [medical examiner's] office."
The autopsies are expected to be done Tuesday.
Police remain on scene at the home and say everyone they've questioned so far has cooperated.