A family’s bedroom curtains caught fire in a freak accident when sunlight reflected on to a make-up mirror.
Firefighters are now issuing a warning to people about the risk of low spring sunlight shining on glass after the fire near Newark.
A crew was quickly on the scene of the blaze at Weston, containing the fire to a corner in the room.
Sunlight on the magnifying mirror caused an intense beam of light which set fire to the curtains.
The same crew also attended a similar incident in Muskham last year in which a mirror set fire to some paper.
Firefighters say these types of fires sometimes happen in autumn and spring as the low sun catches objects left on window sills.
The service is urging people to check what they are leaving around the house, and say even reading glasses are a risk.
Nottinghamshire Fire and Rescue Service Crew Manager, Andy Oxnard, said: “When we talk about magnifying objects we refer to everyday things such as fish bowls, glass ornaments, paperweights and glasses of water, as well as mirrors.
“We would strongly advise that people avoid placing these types of objects near windows as they can potentially concentrate the sun’s rays and set fire to nearby items such as curtains, paper or clothes.”