Initial police enquiries suggest the fire which engulfed a Fairy Meadow townhouse may have been deliberately lit.
A NSW Police spokesman said the initial enquiries suggested the fire was 'suspicious'.
Emergency services were called to the fire in Alexander Street, near Braeda Street at about 4pm on Wednesday.
The spokesman said there unit on fire was unoccupied and no person was injured.
More than 20 firefighters worked frantically to put out the fire.
A Fire and Rescue NSW spokesman said the fire broke out around 4pm in a townhouse, which was in a complex of five townhouses in Alexander Street.
"A full investigation has been completed and no person was inside the premises," the spokesman said.
"The fire has been knocked down but it is still smouldering.
"There are 25 firefighters on site at the moment trying to put out the fire."
A neighbour who didn't want to be named told the Mercury "unit 6 had a fire".
"It's pretty weird. The guy who got kicked out of the place left a massive junk pile," he said.
"I didn't see anyone go in or out. It came up quick.
"It was a hoarders' house. Power went funny. The flames looked so high I thought there must be piles of newspapers in there."
Police, paramedics and Endeavour Energy remain on scene..
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