Eyewitnesses have told ITV News Central a number of loud explosions could be heard from the fire at G&P batteries in Darlaston, Walsall.
50 firefighters are currently tackling the blaze on Willenhall Road.
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A bright and breezy day for most of the midlands, staying largely dry.
East Midlands weather: Cold tonight, dry tomorrow
West Midlands weather: Dry and cloudy tomorrow