Transcript for Was billionaire couple murdered by multiple killers?

The new questions about the deaths of a billionaire couple from Canada. What appeared to be a murder suicide maybe different. What's happening Ron. The couple found dead in their man son in ton hanged. Now private investigators hired by the couple's family say there's evidence pointing in that direction. Reporter: This morning a flurry of police activity in a Toronto neighbor amid a new twist in the mysterious and shocking deaths of one of the world's wealthiest couple Barry and honey Sherman. Private investigating hired by the family believe the pair was murdered by multiple killer. We're just going through our procedure. Reporter: They were found hanged inside their $7 million home in December initially raising questions whether it was a murder suicide. The community stun. They're great people. They've given to the community and done things for people. Reporter: The couple 'macing a $3.2 million fortune. We started this in 1974 almost 40 years ago. Known forgiving tens of millions of dollar tos to charitable causes. Reporter: A real estate agent found the bodies hanging their this indoor pool. There was no sign of forced entry. Cbc Toronto reports the private investigators believe honey Sherman injuries reveal a struggle. The couple's wrist showing they may have been bound togeth. Theyth eagerly await ago trip to Florida, the couple planning the an upcoming party at their home in palm beach. Toronto homicide detectives are recanvasing the neighbor. So far officially police say the Sherman's death appear suspicious. Thanks, Ron. Are we going back to rob again. Should we. Should we is an interesting

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