Peel Regional Police say the man called the Oologah police department on May 31 and made "derogatory comments" about an officer who had been shot in the head during a chase a few days earlier.
Const. Fiona Thivierge says the man was "very irate" on the phone and expressed his dislike of police.
She says he also went on about the injured officer's "potential to die."
Thivierge says the man was arrested for mischief and questioned Monday evening, but police let him go without laying charges.
His name is not being released.
"Basically, he called the police department, he ranted about nasty things, we spoke to him, we released him," Thivierge told The Canadian Press.
"Based on the call, we would never have charged him ... and I don't believe that's what they were looking for," she said.
"I think it was more (to) check on his well-being and see what's going on with him."
-by Paola Loriggio in Toronto
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