Police have confirmed a second person received minor injuries after an apparent explosion at an industrial chemcials unit in West Thurrock, Essex this evening. Both were employees at the site.
Safety experts have declared the area safe and there was no longer any danger to the public, the force added.
The cause of the explosion is being investigated.
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A man, apparently armed with a small axe and a large stick, was detained close to the event and police cleared the area as a precaution.