About 200 firefighters have been deployed to stop a massive factory fire in Sydney's west, with authorities warning it could burn for days.
Emergency services were called to a waste management business in Kurrajong Street, North St Marys at about 10.50pm last night.
Explosions were heard as the blaze began, with some being felt several kilometres away in Penrith.
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A fireball was seen high above the site, reaching 150 metres into the air.
The fire could still burn for several days, as hazardous materials at the business, a recycling centre, is currently feeding the inferno.
One firefighter was treated at the scene for minor burns, with fire crews being praised for their valiant efforts to contain the raging fire.
"There's been some amazing firefighting going on," Fire Commissioner Jeremy Fewtrell said.
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"We've had an incredibly large explosion, and so luckily all of our firefighters were able to be safe through that."
Whilst the cause of the fire remains unknown at this stage, police are conducting their own investigations into the incident.
A 200 metre exclusion zone has been put in place, with motorists urged to avoid the area.
Police are urging anyone with information on the fire or who was in the area at the time with phone or dashcam footage to contact Penrith Police Station or Crime Stoppers on 1800 333 000.
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