A Toronto couple murdered in Florida last month was killed by asphyxiation, the victim of at least two killers, who were likely not known to their victims, police say.
Police in Hallandale Beach released the details Wednesday as they appealed for public help in solving the January double murder of retired snowbirds David Pichosky and Rochelle Wise.
A $51,000 reward is being offered.
Police does not know of a motive for the "senseless" crime, Hallandale Beach police chief Dwayne Flournoy told reporters.
"They both died of asphyxiation in a manner that's a homicide," he said, declining to be more specific.
He said investigators had forensic evidence showing there was more than one killer.
"This was not perpetrated by a sole perpetrator, there's multiple culprits involved in this double homicide," Mr. Flournoy said.
"I'm confident that we're going to solve this case … those people who are responsible for this, their freedom is short-lived."
He added that "we have no reason to believe that the people who are responsible for this homicide were known to them."
The couple had been wintering at their home in Venetian Park, a waterfront neighbourhood favoured by snowbirds in Hallandale Beach, north of Miami.
For the first time, police gave more details about the victims' last days before their slaying.
On Jan. 8, Mr. Pichosky and Ms. Wise, who are modern Orthodox Jews, had been worshipping at a local synagogue, then visited a Walmart outlet that evening, police said, releasing a security video of the couple at the retailing store.
The next day, they couple had an online video chat on FaceTime with relatives, around 8 a.m.
Later that morning, a neighbour's security camera recorded a corpulent woman arriving at the victims' house, carrying an unidentified item. She went to the back of the house then left empty-handed.
Police are still trying to identify the woman, saying she might have witnessed something.
Mr. Pichosky and Ms. Wise were supposed to have lunch that day with friends who lived nearby but they didn't show up.
The next evening, on Jan. 10, the friends used a spare key to enter the house and discovered the bodies.
Mr. Pichosky, a 71-year-old who was known as Donny, and Ms. Wise, 66, were a devout, popular couple who were active in their community and had no known enemies.
Mr. Flournoy said his department initially received a tip that Mr. Pichosky might have been targeted because he went to the local casino.
The police chief said investigators discovered instead that Mr. Pichosky wasn't a gambler and had only been to the casino to buy ice cream for his grandchildren.
Another police theory, about which he did not elaborate, was dispelled after investigators visited the couple's home in Toronto, Mr. Flournoy said.
Ms. Wise's son, Jamie, and a family friend, Pearl Gladman, called on anyone with information to contact police.
"We're looking for any bit of information, anything that anyone might know that could help find the people who did this to my mom and Donny," Jamie Wise said.
"If you know anything, help the family get beyond this," Ms. Gladman said. "Just help us get an end to this."
Mr. Flournoy urged the perpetrators to come forward, saying that their co-operation would lead to a more lenient sentence.
"This case is going to be solved, trust me," he said.
Mr. Pichosky and Ms. Wise lived in North York.
Ms. Wise had been a preschool vice-principal at Bialik Hebrew Day School. She was also a founding director of the Crestwood Valley Day Camp.
Mr. Pichosky was a retired businessman who was an active member of the Shaarei Shomayim synagogue, a Modern Orthodox Jewish congregation.
They married four years ago after meeting on a blind date their children arranged.