The deaths of Canadian billionaire couple Barry and Honey Sherman are being treated as murder, Toronto police say.

The bodies of Mr Sherman, 75, and Mrs Sherman, 70, were found in their Toronto home on 15 December.

Mr Sherman was the founder and chairman of pharmaceutical giant Apotex, which sells generic medicines worldwide.

The new details of the case came on the same day that Apotex announced CEO Jeremy Desai’s resignation.

The company said in a statement on Friday that Mr Desai left the company to pursue other opportunities.

Barry Sherman was one of Canada’s richest men and a prominent philanthropist.

Honey Sherman was a board member for several hospitals, charities and Jewish organisations.

Police say the couple were last seen alive on the evening of 13 December and had no communication with family since then.

They say their investigators found no sign of forced entry on any access points to the home.

Two days later the pair were found fully clothed by the pool “hanging by belts in a semi-seated position on the pool deck”, said Toronto police Detective Sgt Susan Gomes.

Police said they believe the couple were “targeted”.