About 60 firefighters attended the blaze and rescued one man from the roof of the building. Another escaped before crews arrived, the fire brigade said.
The fire caused severe damage to the house and the roof was destroyed. Crews rescued a man from the rear of the house using a ladder.
Both men have been taken to hospital to be treated for smoke inhalation. Our fire investigation unit is now working to find out what caused the blaze.
The building is believed to have been disused. Its roof was destroyed by the blaze and a large section of the ground and first floors were badly damaged, a spokesman added.
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