Watch: BBC reporter at scene of West Midlands sodium cyanide spill
The BBC's Jo Black is by a Walsall canal where approximately 100 fish can be seen dead in the water following a sodium cyanide spill.
People have been urged not to go near a long section of the canal network and connected waterways in Wednesbury, Tipton and West Bromwich.
The Environment Agency (EA) said the sodium cyanide that spilled into the Walsall waterway on Tuesday came from Anochrome Ltd, a firm which deals in surface coatings and sealing.
Wildlife experts said the spillage's impact would be devastating.
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