Police do not know of explicit connections between Mr. Kanagaratnam and the Gay Village, the detective added. His family reported him missing to Peel Regional Police shortly afterwards.
The 66-year-old former landscaper is already facing seven charges of first-degree murder in the deaths of men linked to Toronto's gay community.
Idsinga said Kanagaratnam's remains were found at a home McArthur used as storage for his landscaping business.
The new charge is for the death of Kirushna Kumar Kanagaratnam, who arrived in Canada from Sri Lanka in 2010.
McArthur worked as a landscaper and reportedly hid the remains of some of his alleged victims in flowerpots at a property that he did work for. After receiving assistance from an unnamed worldwide government agency, Idsinga said police were able to identify the victim.
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The witness noted they "were canoodling and being affectionate as she sat on his lap" claiming "they are 100% back together". They walked around the fields together in hugs and later Jeffries was seen resting her head on The Weeknd's shoulder.
"I think we've all seen in the media so-called experts who tell us that serial killers don't start in their late 50s and their 60s", Idsinga said. Authorities said he was allegedly murdered by McArthur sometime between September 3 and December 14, 2015. CBC News reported the image came from McArthur's computer, but Idsinga would not confirm that information.
Police said it was rare for them to release a photo of a potential victim, but they said "good feedback" from the public - including more than 500 tips - helped them identify the man.
The sprawling police investigation, which Idsinga has previously described as unprecedented in size and scope, is now also scrutinizing 15 unsolved homicides that took place between 1975 and 1997.
During this time, McArthur allegedly murdered Mahmudi, a man who lived in Scarborough with his wife and hadn't come out to his family; Dean Lisowick, a sex worker who struggled with homelessness, and Selim Esen, a recent immigrant with few friends.
He emphasized, however, that police have not uncovered any evidence to suggest that McArthur's alleged killing spree began before 2010 when Navaratnam is believed to have died. As recently as six weeks before McArthur's arrest, the force, including Chief Mark Saunders, said there was no indication the disappearances were the work of a serial killer. Police plan to search them once the weather warms in early May.