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.
Less than a week after he was charged with a seventh murder, alleged serial killer Bruce McArthur has been accused of killing an eighth victim.
Kanagaratnam's remains were recovered from planters at a central Toronto home, Idsinga said. He had not been reported missing to any Canadian authorities, but in December 2017, a man who said he was his brother circulated a Facebook post stating that Kanagaratnam hadn't been in contact with his family in Sri Lanka for at least a year.
He said the man was identified through help from an unnamed global agency as well as an unusual photograph police released last month.
Toronto police have scheduled a press conference for 10:30 a.m.to update their investigation.
When asked how police narrowed down a timeframe for Kanagaratnam's death, Idsgina said records assisted police in the timeline but he would not elaborate further. In addition, there was nothing linking him to Toronto's Gay Village, which is where McArthur is alleged to have found his victims, some of whom he had a sexual relationship with.
"We just don't know yet", Idsinga said previously. A statement from the Toronto Police Department said the remains of Kayhan have not been identified.More news: London violent crime: 18-year-old man stabbed in Forest Gate
Later that month, he was charged with the first-degree murder of Majeed Kayhan, Soroush Mahmudi, and Dean Lisowick.
"We have lots of searches left to do as the weather gets warmer", Idsinga said. It closed after 18 months as it did not establish the whereabouts of the missing men or resolve the circumstances of their disappearances, police said.
He also acknowledged the work of the officers on Project Prism.
Idsinga said Kanagaratnam, who was identified with the help of an unnamed global agency, was allegedly killed between September and December 2015.
Police initially released a digitally altered photograph of an unknown deceased man in early March.
A police source previously told CBC Toronto the image of the dead man was among a cache of pictures of alleged victims found on McArthur's computer.