Transcript for Mystery surrounds death of pharmaceutical tycoon and his wife

Sounds like he just snapped. Thanks. The mysterious death of a billionaire couple found hanging inside their mansion they're calling the death of Barry Sherman and his wife honey suspicious saying they were both strangled. Friends and family are in shock. The couple, the shermans were philanthropists, their company employs thousands making generic drugs. Now police want to know who would want them dead. Barry and honey Sherman were one of the world's wealthiest couples worth $3.2 billion thanks to their pharmaceutical company. We started apotex 14 years ago. Reporter: Known for giving money to charitable caughts. We wanted to make sure that future generations would have a place they could call home. Reporter: But this morning a community in shock. After a real estate agent preparing for an open house reportedly found the pair hanging from a railing near this indoor pool. Inside their more than $5 million Toronto home. The house had recently gone on the market. Police say the cause of death was ligature neck compression. The homicide unit has now taken the lead in the investigation. Despite some initial questions about a possible murder/suicide. Those who knew them best say no way. They were great people and have given to the community and done things for people. Made people's lives better. Reporter: According to friends of the couple they were both eagerly awaiting a trip to Florida. Honey Sherman had recently sent an e-mail saying, I am coming south Monday, December 18th to Friday January 12th. Several friends say they received an invitation to a party the couple were planning at their home in palm beach. Police say there was no sign of forced entry. Police will draw a circle around both of them. They're going to look at their personal lives and professional lives and their social lives. They're going to look at all of that. Reporter: The shermans were well connected in Canadian politics. Prime minister Justin Trudeau tweeting his condolences to everyone touched by their vision and spirit. The shermans had four children and a grandchild. The family is urging police to conduct a thorough criminal investigation. Barry Sherman had been involved in a number of lawsuits including one brought by his own cousins who claimed they had been cut out of the family business. A lot of questions to answer in this one. Thanks very much.

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