UPDATE: Police say the 16-year-old has died in hospital.
The NRP is still investigating the cause of the fire alongside the office of the Ontario Fire Marshall and the Coroner.
Anyone with information should call 905-688-4111 with extension 4233.
A 16-year-old had to be taken to an out-of-town hospital with serious injuries after a house fire in Thorold.
Police say it happened in the Maitland Street and Colborne Street area Saturday morning.
A 70-year-old woman was also taken to hospital for minor injuries.
The NRP is investigating alongside the Ontario Fire Marshall.

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