Central York Fire Services is investigating the cause of a Thursday afternoon house fire on Wildwood Drive in Newmarket.
The fire department contacted the Ontario Fire Marshal after a firefighter suffered a leg muscle injury, was taken to hospital and released, according to an incident report.
Heavy smoke and flames were seen coming from the home in the area of Leslie and Srigley streets, after 3 p.m.
The fire then spread to the interior of the house.
Two residents were home at the time but managed to escape without injuries.
The house needs repairs before occupants can return, the report said.
They have temporary accommodation.
Several firefighting crews responded to the fire.
They worked with York Region Paramedic Services, York Regional Police and utility companies.