Tributes poured in from prominent Canadians, including Prime Minister Justin Trudeau, after the sudden deaths of billionaire pharmaceutical executive Bernard "Barry" Sherman and his wife shocked the country's corporate and political worlds.
Authorities have not said who made the call, though Canadian media reported the couple's bodies were found by a real estate agent helping them sell their home, which was on the market for $C6.9 million (about $A7 million).
Called to the house to attend a "medical complaint" at around midday on Friday, officers said they found no signs of forced entry to the home.
"The circumstances of their death appear suspicious and we are treating it that way", said Constable David Hopkinson.
Two bodies covered in blankets were later seen being removed from the house.
In 1974, Sherman used his mother's life savings to buy his uncle's drug company with initially just a couple of employees and 5,000 square feet of area.
Sherman faced legal action from family members alleging they had been cut out of the company over the years. He is estimated to be worth almost $5 billion and is believed to be the 15th richest person in Canada. Sherman and his wife have four children together.
Mrs Sherman sat on the boards of several hospital, charitable and Jewish foundations, and last month was awarded a Senate medal for community service.
Apotex described their deaths as shocking and tragic, while other statements praised the Shermans' numerous philanthropic efforts.
Outside of the pharmaceutical business, the Shermans were also known for their philanthropy. "Our condolences to their family & friends, and to everyone touched by their vision & spirit". Neighbours confirmed that the property was the couple's home.
Police have not released any names but the province's Health Minister Eric Hoskins, tweeted about the deaths writing "I am beyond words right now".
"Barry and Honey were kind, good people who will be greatly missed. A very, very sad day", he wrote.
"I hope that investigation will be able to provide answers for all of us who are mourning this tremendous loss", he said.