Toronto police are sifting through planters, flower pots and backyards throughout the city for the possible remains of victims of an alleged serial killer who works as a landscaper and is accused of murdering at least five people, PEOPLE confirms.
On Monday, Bruce McArthur, 66, was arrested and charged with first-degree murder in the deaths of three men who had been previously reported missing, Toronto Police Det. Sgt. Hank Idsinga said at a press conference.
His arrest came after investigators found the dismembered, skeletal remains of three unidentified victims “hidden at the bottom of planters” at a home McArthur used as storage for his landscaping business, Idsinga said.
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Police are searching for the remains of more possible victims.
“The city of Toronto has never seen anything like this,” Idsinga said. “It’s a serial killer. An alleged serial killer. He has taken some steps to cover his tracks and we have to uncover these victims and identify these victims.”
Authorities do not yet know if the remains found in the planters are those of the men McArthur is accused of killing, said Idsinga, adding that the remains are being tested for DNA.
McArthur, who had reportedly played Santa Claus for the past several years at a local mall, had already been charged on Jan. 18 with first-degree murder in the presumed deaths of two other men: Selim Esen and Andrew Kinsman, who were both reported missing from the city’s Gay Village area last year, Idsinga said.
McArthur was arrested Monday in connection with the deaths of Majeed Kayhan, a 58-year-old immigrant from Afghanistan, who was reported missing by his son and is believed to have been killed on or about Oct. 18, 2012; Soroush Mahmudi, 50, who was reported missing by his family and is believed to have been killed on or about Aug. 15, 2015; and Dean Lisowick, 47, who lived at a shelter and was never reported missing, Idsinga said. Lisowick is believed to have been killed between April 4, 2016, and March 15, 2017, Idsinga said.
“All of the families are, of course, shocked,” he said.
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In their search for more possible victims, police plan to excavate at least two sites associated with McArthur’s work, Idsinga said.
“We do believe there are more (victims),” Idsinga said. “I have no idea how many more there are going to be.”
Calling the large-scale investigation “unprecedented,” Idsinga said a team of investigators has been working alongside scores of officers, canine unit members and personnel searching 30 properties to which McArthur is linked, he said.
“We have seized planters from all over the city,” he said.
He called upon any of McArthur’s customers who have not been contacted police to come forward.
Authorities believe the killings began in 2012, Idsinga said.
Idsinga wouldn’t comment on what McArthur has said to investigators.
Idsinga had previously confirmed that McArthur was known in Toronto’s Gay Village and was in a relationship with Kinsman, the Toronto Star reports.
Idsinga wouldn’t comment on McArthur’s connection to the other victims or how police believe the men were killed.
McArthur remains in police custody and will appear in court via video on Feb. 14.
PEOPLE’s calls for comment from his attorney were not immediately returned.