York Regional Police said the heads were found at various locations in Stouffville, a town of 25,000 population about 28 miles northeast of Toronto, the Canadian Broadcasting Corp. reported Thursday.
The incidents, between Aug. 12 and Sept. 13, are not believed to be the result of a predatory animal, police said in a news conference.
In all but one case, the heads were found without any other remains.
The Ontario SPCA is assisting York Regional Police in its investigation.
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