A two-year-old toddler has shot dead his 29-year-old mother at a Walmart store in America after reaching into her handbag and accidentally firing her gun.

The mother was shopping with her son and three other children at the store in the state of Idaho when she was shot on Tuesday morning, local time.

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In a statement, the Kootenai County sheriff’s office said the boy was sitting in the front of the shopping trolley when he found the gun and accidentally shot her.

Authorities said the woman’s name will not be released until all her family are notified.

Employees evacuated the Walmart after the shooting, which occurred at the back of the store in the electronics section.

The sheriff’s office said the woman had a concealed weapons permit allowing her to carry the gun.