CALGARY — A man suspected of strangling his wife and burying her body in the house they shared told an undercover officer he found his hands around her neck during a heated argument and "then she was gone."
Allan Shyback, 40, is charged with second-degree murder and causing an indignity to a body in the death of Lisa Mitchell, 31, who was last seen alive in October 2012.
An undercover "Mr. Big" sting operation, dubbed "Operation Aurora," was launched in 2013 and ended with Shyback's alleged confession and arrest in Winnipeg a year later.
A recording was played in court in Calgary on Thursday after Shyback received a call in 2014 from a Calgary police officer, telling him Mitchell's case was now considered a homicide and officers intended to search his house in the city.
"You good buddy? You look like you just ... saw a ghost. What's going on?" the undercover officer asked after Shyback got the phone call.
Shyback told him he and Mitchell had a heated argument and she had lunged at him with a knife.
"She said she could probably put me in the hospital and tell them it was self defence. She'd get the kids and everything else and I'd be in jail," Shyback can be heard saying.
"I pushed back at her. At some point my hands were around her neck. I remember trying to let go, trying to stop. And then she was gone.
"I can remember trying to make myself let go."
Shyback initially panicked after he received the call from Calgary police.
"I've got to get out of here," he muttered.
The undercover officer suggested that perhaps they wouldn't find Mitchell's body.
"Not if they're seriously looking," said Shyback.
"There's still a chance," said the officer.
"Uh, no. If they go and look right now."
Shyback said he buried Mitchell under cement in the basement. He worried about getting caught but said it was months before police called him.
"I was expecting things to fall apart, especially during that first year."
Mitchell's partially mummified body was later found in a plastic container buried under cement in the basement.
Earlier on Thursday, another undercover officer told court he was tasked with befriending Shyback. He told him about a friend who was opening an auto brokerage and offered him a job.
The ruse continued with another officer, pretending to be his girlfriend, babysitting Shyback's children.
Shyback was more than willing to talk about his ex.
"He indicated that she had been gone for some time now ... approximately two years and he was having trouble figuring out what to tell the kids. Specifically, why she had gone and where she had gone," he said.
"Shyback indicated he honestly thinks his ex being gone is the best thing for he and the kids."
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