The fire started at a factory on Hampton Park Road in Hereford at around 8am.
Some residents in the nearby area have been evacuated to Hereford Leisure Centre on Holmer Road.
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Tributes have been paid to a 91-year-old Royal British Legion member who died in a house fire on Saturday morning.
Flood warnings have been issued across the Midlands after heavy rainfall.
Most parts across the region will be dry but showers are likely as well as brisk winds.