Three fire engines from Rivelin and Central station were called out to a house fire on Sale Hill, Sheffield at 1:37am today.
When fire crews arrived, they found the elderly occupants safely at the front of the property.
The fire was caused by an old microwavable hand warmer which had been left on the mattress, setting it alight. The smoke logged ground floor was ventilated by crews, and the burnt item was cut away from the mattress.
Be careful when using microwavable heat sources, and avoid using old ones where you can.