Billowing plumes of acrid black smoke could be seen 60 miles away as crews fought to control the blaze at the recycling plant in Smethwick containing 50,000 tons of plastic.
Roads have been closed, buses diverted and a school shut by the huge blaze, while 11 firefighters have been treated for heat exhaustion, smoke inhalation, eye injuries and a minor burn caused by the ferocity of the inferno. Ambulances have been on scene throughout the night and today, and took three of the injured firefighters to hospital.
The blaze has engulfed the Jayplas factory unit, in Dartmouth Road, sending flames shooting more than 6,000ft into the sky and causing plumes of acrid smoke that could be seen from as far away as Kettering in Northamptonshire.
On Monday night, Mike Maxwell, operations manager at Jayplas, said: "This is a tragic accident over which we've had no control. Jayplas would like to thank the emergency services for their speedy response and dealing with this incident in an extremely professional manner. I'd also like to thank our staff on site for raising the alarm as soon as they were aware of the fire, which allowed the fire brigade to act so quickly and reduce the severity of this incident."
West Midlands Fire Service said nearly 40 engines had been at the scene, including seven from Staffordshire Hereford & Worcester.
The fire service said CCTV showed the blaze had been sparked by a single Chinese lantern that landed on top of bales of plastic being stored at the site.
As the fire continued to rage, chief fire officer Vij Randeniya urged people not to use Chinese lanterns and said that the service had been campaigning for their use to be regulated. More than 400 emergency calls have been made about the blaze, and people have been urged only to call 999 if it is completely necessary as under-pressure crews continue their fight to contain the blaze.
The Environment Agency said it was "optimistic" that a neighbouring canal, which is a popular fishing spot, would not be badly affected.
Eyewitnesses described the devastation at the site as people from miles around took photographs and film footage of the chaotic scenes. Residents living near to the blaze and night-shift workers at nearby factories flocked outside to get a glimpse of the fire after it took hold just after midnight.
Eyewitness Ian Dangerfield, a documentary maker, said: "It was unbelievable. I could smell smoke and saw a huge cloud and I thought, 'there's no way that's a big thunderstorm'."
The 46-year-old, of Esher Road, West Bromwich, added: "I went out the front door and could see the smoke going across the sky so I grabbed my camera. Police were stopping cars. It was absolute chaos. I've never known anything like it in my life."
Retired photographer Nick Greasby heard loud bangs from his home in nearby Great Arthur Street and rushed out of his home in his dressing gown to investigate. The 71-year-old said: "I saw the flames and I couldn't believe it. They were strong and you could see smoke billowing over the trees and houses."
Staff who arrived at Galton Valley Primary School in Brasshouse Lane, Smethwick, were evacuated as firefighters continued the mammoth challenge of keeping the flames under control. Pupils have been told to stay at home.
Firefighters from the whole of the West Midlands force are battling the blaze while crews have also been drafted in from across the border in Staffordshire.
Public Health England this afternoon urged motorists who must travel through the smoke to keep their windows closed and turn off air conditioning.
This afternoon, West Midlands Fire Service called for an urgent review of the legislation regarding the use of airborne lanterns.
It said there was evidence of them causing fires, wasting emergency services' time, being mistaken for distress flares, misleading pilots and causing environmental damage.
They also pose a risk to livestock, agriculture, camping activities, recycling sites and hazardous material sites.
A spokesman for the service said: "We do not support the use of these devices, and ask that members of the public and event organisers stop using them.
"Internationally, certain brands of fire lanterns have been banned and there has been a temporary ban on all such products in Australia following a series of wildfires.
"We believe there is wide scope for limiting the potential effects, use and design of such lanterns, and for the exploration of legal action being taken by people adversely affected by them.
"We also question whether event licences should be issued for events from which it is planned to launch such lanterns."
For five pages of special reports and pictures, see tonight's Express & Star.
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