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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As the sun sets on September it looks like it's been the driest since records began, but a change is on the way for the start of October
It will be mainly dry with bright or clear spells.