Photo: CTV

A 10-month-old boy is dead due to what police believe was a carbon monoxide leak in a home in Barrie, Ont.

Police say the boy's 30-year-old mother is in critical condition in a Toronto hospital and her two-year-old daughter is in stable condition.

Police and firefighters were called to the home just after 8:30 a.m. Sunday.

The woman's husband had called 911 after arriving home to find his wife and infant boy unresponsive and his daughter alert, but showing signs of carbon monoxide poisoning.

The baby boy was pronounced dead at a local hospital.

No names have been released and both Barrie police and the Office of the Chief Coroner are investigating.