A four-alarm fire that destroyed a neglected home and damaged a neighbouring residence in downtown Toronto is being investigated as a possible arson, police say.

In an update Friday, police initially said the fire was deliberately set, but corrected that information a short time later by saying the blaze remains under investigation by the Office of the Fire Marshal and is considered suspicious.

Firefighters spent hours battling the stubborn fire in a century-old rowhouse on George Street, just north of Dundas Street East, after it was reported early Thursday morning.

Because the flames spread into the walls and roof, it took about four hours for Toronto Fire Services to bring the blaze under control.

By the time the fire was extinguished, more than 80 firefighters were involved in the fight.

Investigators consider the fire to be suspicious because it occurred in a derelict building that was frequented by squatters.

The owner was not insured and will likely be responsible for covering the cost of the demolition, city officials told CP24.

The lone injury reported was a twisted ankle suffered by a firefighter when he stepped on debris in an alley. Two cats were rescued from a neighbouring building.

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