Businesses near a chemical factory that went up in flames in Melbourne’s west will remain closed overnight, with smoke from the explosion expected to linger for days.
Almost 200 firefighters responded to the fire on Swann Dr, Derrimut, that is believed to have been caused by a chemical explosion.
WATCH THE VIDEO ABOVE: Crews battle raging factory fire in Melbourne’s west.
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Large metal drums filled with chemicals were thrown into the air from deep within the blaze, posing a danger to crews battling the flames.
The fire was deemed under control at 3.30pm, about four hours after crews initially arrived at the scene.
No injuries have been reported and it is believed everyone inside the building was evacuated safely, Victoria Police said.
Hazardous material and toxins were burning, with the Western Freeway closed for several hours near the area for health reasons, according to Fire Rescue Victoria.
Deputy commissioner Michelle Cowling said the factory included a warehouse that mixed chemicals and stored drums containing kerosene, fuel, methylated spirits, methanol and others.
The blaze was Melbourne’s most significant in several years and would likely burn for days, she said.
“We’ve got embers burning, fire burning – until we can get close enough even with our aerial appliances that are on site and specialist hazmat people on site we can’t get in close enough to cool this fire down,” she said.
She said an acrid smell was expected to linger and advised people to stay away from the area over coming days if possible.
Fire investigators have not yet confirmed how the blaze started but it did not spread to nearby buildings.
Specialist crews and agencies remain on site, such as the Environment Protection Authority and Fire Rescue Victoria’s hazmat and scientific advisers.
A Watch and Act has been downgraded to an Advice but businesses on Swann Dr and Bliss Ct will remain closed overnight.
FRV does not want people exposed to the wastewater and toxic smoke “and they cannot return until it is safe to do so”, FRV said Wednesday evening.
The agency said earlier that hazardous materials and “unknown toxins” had been burning within the building.
“A large plume of smoke is blowing over the eastern and western suburbs of Melbourne,” FRV said.
“Anyone located in the area affected by smoke should take shelter indoors immediately.”
Factory site of previous fatal explosion
The ACB Group factory is the site of another chemical explosion last year in which a man was killed.
At least 30 people managed to evacuate however the body of a 44-year-old Hoppers Crossing man was found inside after the blaze was extinguished.
One other worker suffered minor injuries.
All lanes of the Western Fwy were previously closed between the M80 Ring Rd and Ballarat Rd.
Drivers on Mt Derrimut Rd have been told to expect delays.
Errin Morton, who drove past the blaze, told 7NEWS.com.au she could feel the heat from the fire coming through the car.
“(The) windows were hot and (there was) a really strong chemical smell,” she said.
WorkSafe has been contacted for comment.
– With AAP