A Canadian billionaire and his wife have been found dead in the basement of their Toronto mansion.

Police have said they are treating the deaths of Barry Sherman, 75, the founder of Canadian drug company Apotex, and his wife Honey as “suspicious”.

Their bodies were discovered by an estate agent who was setting up an open house for the luxury property, which had recently been put up for sale for $6.9m Canadian dollars (over £4m).

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.

Homicide detective David Hopkinson said: “The circumstances of their death appear suspicious and we are treating it that way.”

Two bodies covered in blankets were later seen being removed from the house.

One of the nation’s wealthiest couples, they had given tens of millions of dollars to hospitals, universities and Jewish organisations and were fundraisers for Prime Minister Justin Trudeau’s Liberal party.

In response to the news of their deaths, Mr Trudeau tweeted: “Our condolences to their family & friends, and to everyone touched by their vision & spirit.”

Mr Sherman had set up the pharmaceutical company Apotex in 1974, stepping down as chief executive in 2012 but remaining executive chairman.

Lawsuits from family members, alleging they were cut out of their share of the company back in 1967, had dogged Mr Sherman for decades.

Calling the deaths “tragic”, Apotex tweeted to say everyone at the company, which employs around 16,000 staff worldwide, was “deeply shocked and saddened”.

Forbes magazine estimated Mr Sherman’s personal net worth at $3.2bn (£2.4bn), making him the 15th richest Canadian.

The couple leave behind four children.

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