More than 100 firefighters are tackling a blaze at a large industrial unit in Essex as a "significant incident" is declared.
People living near the site between East Hanningfield and Rettendon are being told to keep their windows and doors closed as footage shows a vast plume of black smoke and visible flames above the building.
Essex County Fire and Rescue Service also told people to "avoid the area if you can".
Colin Neale Jr was driving along the A13 near Dagenham when he saw the plumes of smoke.
He told Sky News that, as he drove closer, he realised how big the fire was and decided to send his drone up over the fields.
Mr Neale said the drone showed "multiple fields" had caught fire and it appeared two industrial complexes were affected.
A spokesman for East of England Ambulance Service said its hazardous area response team had gone to the scene.
Essex County Fire and Rescue Service area manager Dave Bond said: "The incident has been declared a major incident by the fire service due to the size of the fire that we're dealing with...
"There is still significant smoke... and we're advising people to stay away from the area while we deal with it."
Mr Bond added: "We do believe that we've got the fire surrounded now, but we ask for the public's patience while we extinguish the fire and bring the incident to a closure."
It is not yet known if there have been any injuries.
(c) Sky News 2026: 'Significant incident' as more than 100 firefighters tackle massive blaze at industrial site in Essex
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