Authorities in Toronto are seeking the latest charges against a man accused of killing multiple men while working as a landscaper.

As CBS News reported, 66-year-old Bruce McArthur was arrested last month on suspicion of two murders.

Both victims — 49-year-old Andrew Kinsman and 44-year-old Selim Esen — were last seen in Toronto’s so-called Gay Village last year.

He was soon charged with the murders of 50-year-old Soroush Marmudi, 58-year-old Majeed Kayhan and Dean Lisowick, a homeless prostitute thought to be in his mid-40s.

According to CNN, police believe McArthur buried the remains of his victims in planters on the property of his landscaping clients.

Most recently, authorities have filed murder charges against McArthur involving a sixth murder victim, 40-year-old Skanda Navaratnam.

Those close to the suspect said he was Navaratnam’s employer and was engaged in a sexual relationship with him when he disappeared in 2010 while leaving what was at the time a gay bar.

The Sri Lankan refugee was later identified through analysis of his dental records.

According to police, McArthur has been employed at dozens of areas in the Toronto region, including some of its most affluent communities, and they expect to find the remains of additional missing persons related to his alleged murder spree.

“There’s hundreds of outstanding missing persons occurrences that we’re looking at,” said Toronto Detective Sgt. Hank Idsinga Idsinga. “We are tracing his whereabouts as far back as we can go.”

[Selim Essen, Sorush Mahmudi, Dean Lisowick, Andrew Kinsman, and Majeed Kayhan/Toronto Police Service via Associated Press]