Remains of 6 people found in planters at property connected to alleged serial killer

— -- More charges are expected in the future for an alleged Toronto serial killer who police say hid the dismembered remains of several people in the bottom of large flower planters.

Last month, self-employed landscaper Bruce McArthur was charged with the deaths of five men, according to Toronto police. He was initially arrested and charged with two deaths on Jan. 18, but he was hit with three more charges later in the month, Meaghan Gray, spokesperson for the Toronto Police Service, told ABC News.

The excavation of a property on Mallory Crescent in Toronto, where police now say that a total of six sets of remains have been found in planters, will begin Friday, Gray said. Investigators believe that McArthur used the property as a storage facility, she said.

One set of remains has been identified as Andrew Kinsman, 49, one of the two men whose deaths McArthur was first charged with, along with 44-year-old Selim Esen, Gray said. Kinsman was reported missing last June, while Esen was reported missing months earlier, in April, according to police.

On Jan. 29, McArthur was additionally charged with first-degree murder in the deaths of Majeed Kayhan, 58; Soroush Mahmudi, 50; and Dean Lisowick, 47, police said. Kayhan was reported missing in 2012, while Mahmudi was reported missing in 2015.

Lisowick was never reported missing, but police said he was likely killed between May 2016 and July 2017.

None of the other remains have been identified yet, Gray said, adding that they could be a combination of new victims and remains of some of the other four men McArthur is already charged with killing.

Investigators also looked into several other properties McArthur is "closely associated" to, Gray said. In addition to the property on Mallory Crescent, authorities are searching a property in Toronto's Thorncliffe Park neighborhood. Three other properties that McArthur allegedly serviced "have been released back to their homeowners," Gray said.

Other locations could be investigated as well, Gray said. Authorities have seized planters from other properties but have not yet discovered whether they contain any human remains.

More remains could be found at the Mallory Crescent property when investigators begin to dig with the assistance of a forensic anthropologist, Gray said.

At least one of the men McArthur is charged with killing went missing from Gay Village, a predominantly gay neighborhood, Toronto Police Sgt. Hank Idsinga said last month. But, Idsinga emphasized that the case "encompasses more than the gay community."

It "encompasses the city of Toronto," he said. "The city of Toronto has never seen anything like this."

McArthur made a brief court appearance on Jan. 19 after his arrest and is currently being held in a Toronto jail. It is unclear when he will appear in court next, Gray said.

ABC News could not immediately reach an attorney for McArthur for comment.

ABC News' Ben Gittleson and Emily Shapiro contributed to this report.