A massive fire has broken out at a warehouse factory in Guildford, sending flames 40 metres into the air.
More than 130 firefighters are on the scene on Hyne Road, at a factory believed to be owned by waste management company Cleanaway.
Heavy smoke from the fire is blanketing surrounding suburbs, causing the Department of Fire and Emergency Services to issue a smoke alert for residents in South Guildford.
Staff at nearby businesses have been evacuated as fire personnel battle to get the fire under control.
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Motorists have been warned to take care while driving in the area and to turn on their headlights.
Hyne Road has been closed and people are being warned to avoid the area.
At this stage the cause of the fire is not known, but the blaze is so intense that smoke can be seen as far away as the CBD.
Watch in the video below: Massive factory fire in Sydney