Transcript for Death of Canadian billionaire couple ruled murder

It will be awesome to watch. First the deepening mystery over a murder. First there was speculation it was a murder/suicide. Now police are calling it something much different. Reporter: Their deaths shocked the community and family now calling for justice. Now for the first time police say honey and Barry Sherman were targeted and murdered in their Toronto home. This morning, police now calling the mysterious deaths of one of the world's wealthiest cups a double homicide. I'm saying that the shermans were targeted in this event. Reporter: The case initially sparking questions of a murder/suicide. Authorities now say billionaires honey and Barry Sherman were both murdered. Their estate turned crime scene. Figured it was a double murder because of the manner and meth nod of how they died and ligature marks on their wrists which suggests they were tied up before killed. Reporter: Found dead in midler-december by a real estate agent preparing for an open house at their sfrauling three-store $7 million mansion. Hanging by belts from a poolside railing in a semi seated position. On the pool deck. They were wearing their clothing. Reporter: Homicide detectives keeping a tight lid on their investigation. I'm not going to discuss any motives. Reporter: Friday giving this clue about a possible lead. A person is outstanding for this event. Reporter: The shermans built a $3.2 billion pharmaceutical empire. When we started apotex in 1974 almost 40 years ago -- Reporter: Philanthropists known for giving tens of millions to charity. Wanted to make sure that future generations would have a place that they could call home. Reporter: Their children convinced from the outset their parents were both victims. Ordering an independent autopsy and now saying the announcement by the Toronto police service that the tragic deaths of their parents are being investigated as a double homicide was anticipated. Police say their investigation took six weeks partially because of the size of the shermans'home combing through hundreds of hours of silver video and canvassed a second property, guys, outside of Canada. Horrifying story. Erielle, thank you very much. Let's check the weather yet

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