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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A dull and damp day, with cloudy skies and further outbreaks of rain, locally heavy during the morning.
It will be a cloudy day across the West Midlands with showery outbreaks of rain, possibly heavy in places
Low levels of pollen today and tomorrow.