Peel Region police say the mother brought the incident to their attention after she found a vacuum-sealed bag containing what appeared to be marijuana in a box carrying an Angry Birds game.
Const. Thomas Ruttan says the substance has been sent to a lab for tests to confirm if it is in fact marijuana.
He says police went to the Target store in the Brampton, Ont., area and found no other toy boxes containing drugs.
Officers will now be going through video surveillance footage and purchase records at the store to figure out if the box with the apparent drugs had been tampered with in any way.
Ruttan described the incident as "not your everyday occurrence."
Target was not immediately available for comment.
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