A fire which caused serious damage to a Wisbech flat was caused when the sun was reflected on combustible materials.
The fire was started at about 1.25pm today - the hottest day of the year so far - in Orange Grove, Wisbech.
A number of roads were closed while crews worked at the scene.
A Cambridgeshire Fire and Rescue Service spokesman said: “A fire had broken out in the roof space of a second floor flat. Four firefighters wearing breathing apparatus used two hose reels and a jet to extinguish the fire. Firefighters cut away at the roof and dampened down the area. The fire was fully extinguished by 2.55pm.
“The residents of the property were out safely on the arrival of the fire service.
“A fire investigation has been carried out and the most likely cause was accidental, believed to be sunlight reflected on to combustible materials.”
Station Commander Mick Jackman said: “The first crews in attendance worked very hard and did an excellent job to cut away the roof material, extinguish the fire and prevent it from spreading.”