The incident took place at a cottage between the Rendevous pub and the Cork Technology and Business Park, near Mount Mercy school. The scene was being preserved this morning with a technical examination due to be carried out today.
Gardaí have not released the identity of the woman as they seek to investigate the incident.
Emergency services received a call at 9.20pm last night and five units attended the scene.
Gardaí had to divert traffic at the Rendevous Bar and Leesdale, as smoke from the building made driving conditions hazardous.
Local resident Mick Murphy witnessed fire crews arriving at the scene. “You couldn’t even see through the smoke, it was that bad.”
“There was a lot of banging going on. Whether it was the fire brigade breaking down doors, or something exploding. The smoke extended from the Model Farm Road to the Straight Road,” he added.
Local Councillor Mary Shields said the news was very tragic. “It’s frightening and we must be very careful about ensuring elderly people are safe in their own homes and all fire regulations are adhered to in houses,” she said.