A concerned citizen saw the child Aug. 15 and called police.
But the vehicle was no longer in the parking lot when a child-at-risk team arrived.
Edmonton police investigators believe the five-year-old boy had been secured in the back seat, but managed to get out.
The windows in this case were left down in 20-degree weather, but it's simply not safe to ever leave a child alone in a vehicle, Sgt. Gary Willits said Thursday.
"The fact is that while this child was unsupervised, he was revving the motor, could have put the vehicle potentially in gear, could have wandered away from the vehicle, could have fallen out of the vehicle," Willits said.
Police allege the child was left alone for about 30 minutes while the mother was shopping.
A 33-year-old woman is charged with abandoning a child and wilfully causing a child to be in need of intervention.
— With files from CHED Radio
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