Toronto police detective Hank Idsinga said on Friday they believe Mr McArthur will face more charges. The Toronto man was a subject of Project Prism, and police have said he had a sexual relationship with McArthur.
Earlier this month, police identified Andrew Kinsman in the human remains, using fingerprints.
Alleged Bruce McArthur victims, clockwise from left, Majeed Kayhan, 58; Dean Lisowick, 47; Soroush Marmudi, 50; Selim Esen, 44 and Andrew Kinsman, 49.
Idsinga says Navaratnam's remains - and those of five other people - were found in large planters at a residential property where 66-year-old McArthur worked as a landscaper.
December 8, 2017 - Police Chief Mark Saunders says the force will review its practices in missing persons investigations.
The self-employed landscaper was arrested on January 18 and charged with two counts of first-degree murder in relation to the disappearance of Kinsman and Selim Esen.
He added that police are tracing McArthur's whereabouts "as far back as we can go".More news: BHP Billiton (BHP) Rating Lowered to Hold at Citigroup
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Navaratnam, 40, went missing in the Church and Wellesley area after leaving Zipperz, a bar in the gay village in 2010.
Meanwhile, police are now investigating what they believe is a murder scene in McArthur's apartment on the 19th floor of his building at 95 Thorncliffe Park Dr.
In 2017, the disappearances of Kinsman and Esen drew fresh outcry from the community.
They later added three more first degree murder charges in the deaths of Majeed Kayhan, Mahmudi and Dean Lisowick. Excavation at that property ended on February 14 and the home was released back to its owners after officers said no other human remains were found.
He said police have also identified at least two properties for potential excavation, but said forensic test results are needed before they can proceed.
Excavation at the Toronto home where McArthur stored items for his landscaping business - and where the planters were found - ended on February 14, and the home was released back to its owners.