Derbyshire Fire and Rescue received a number of calls around 3.30pm today after reports of an explosion at a disused Thornton's factory in Belper.
People were reported to be inside the building at the time of the explosion but everyone is accounted for.
Fire crews are now damping down and the fire is under control.
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The murder of a frail, 93-year-old pensioner who was savagely beaten as she lay in bed three years ago is still no nearer being solved.
CCTV has been released after a robbery in Saltley supermarket.
Dry on Tuesday with increasing amounts of sunshine developing.