A Toronto couple who was slain in Florida earlier this year died of asphyxiation, police announced Wednesday as they renewed their appeal for tips to solve the double homicide.

Investigators believe at least two people were involved in the killings of Rochelle Wise, 66, and her 71-year-old husband, David "Donny" Pichosky, who were found dead in their winter home in Hallandale Beach in January.

“This was not perpetrated by a sole perpetrator. There’s multiple culprits involved in this double homicide," Hallandale Beach Police Chief Dwayne Flournoy said at a news conference. "And as we begin to release details more and more you will find how senseless this murder is.”

Flournoy said police do not know if the killings were random or if the grandparents were targeted.

In an emotional plea, Wise’s son Jamie urged people who have information about the double homicide to share it with investigators.

“We are looking for any little bit of information,” he told reporters.

He described his mother, a former camp director and school principal, as a woman who loved working with kids and their parents, and was just beginning to enjoy retirement after marrying Pichosky about four years ago.

“She loved children, she loved the parents, too. She loved that aspect of her job, engaging with people,” Jamie Wise told reporters at the news conference. “She had worked hard her whole life and finally found love, and was just starting to taste some of the benefits of hard work that we all do during our life.”

In a bid to generate tips, a $51,000 reward is being offered by Crime Stoppers for information leading to the arrest and conviction of the suspects, as police try to establish a motive for the killings.

“We just need that one break or that one piece to the puzzle so that we can fill it all in,” said Flournoy, who revealed new details about the couple's last moments and the hunt for their killers.

Flournoy said the retired couple visited a local Jewish temple and then went to a Walmart before returning home on the evening of Jan. 8.

The following morning, they spoke to a family member during an online video chat at about 8 a.m., which was one of the last times they were seen alive, Flournoy told reporters.

On Jan. 10, neighbours became concerned when Wise and Pichosky failed to show up for a scheduled lunch meeting. Their bodies were found when the neighbours checked the home.

In February, police released surveillance video of a woman, who was carrying an object as she walked to the rear of the couple's home on Jan. 9.

The video, captured by a neighbour's camera, then shows the woman empty-handed as she walked back to the front/side of the residence.

As of Wednesday, police are still trying to identify the woman and they do not know if she was involved in the double homicide or witnessed anything, Flournoy said.

In an attempt to ease any fears, Flournoy assured Hallandale Beach residents that he has assigned plenty of resources to the investigation, and he said he is confident his detectives will solve the case.

At the news conference, Wise’s longtime friend, Pear Gladman, explained her grief over the death of the woman she considered a sister.

“When the phone rings and it’s a long distance ring I still think it’s her,” Gladman told reporters. “She was as close to a sister as I would ever get.”

Gladman urged people to call detectives if they have any information.

“Whatever anybody knows, just think if it was your family or if it was somebody that you loved,” Gladman said.

Police are asking anyone with information to call detectives at 954-457-1438 or Crime Stoppers anonymously at 954-493-TIPS (8477).

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