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SYDNEY - Three Sydney houses have been destroyed by fire on Christmas Day, leaving families homeless.
Separate fires yesterday ripped through a house and a unit in northwest Sydney and a house in the city's southwest.
A family of six saw their house in Chrysanthemum Avenue at Casula destroyed.
The roof of the two-level brick building collapsed in the blaze, followed by the second floor as fire spread through the air-conditioning duct.
There was extensive smoke and water damage to the rest of the home.
A NSW Fire Brigade spokesman said five crews worked to bring the blaze under control after the family called for help at about 5.30pm (7.30pm NZT).
"The fire was well alight when the fire services attended," he said.
"Fire spread through the air-conditioning duct, this is common, but it is too early to say what caused the blaze."
All six family members, aged between three and 33, were evacuated safely, police said.
In a separate incident in Sydney's northwest, a 35-year-old man and a couple aged in their 70s were in their home in Wildara Avenue at West Pennant Hills when a fire broke out.
The younger man told police he heard a noise about 11.30pm (AEDT) and when he and his mother investigated they discovered the lounge room on fire.
Six trucks from the NSW Fire Brigade attended and safely evacuated the family from the building.
The top floor of the building was destroyed along with most of the family's possessions, police say.
There was significant damage to lower parts of the home.
The cause of the fire is still unknown.
The third blaze broke out last night at a unit in Yates Ave at Dundas, also in Sydney's northwest.
A single unit was destroyed and another unit in the block of six was damaged.
Six trucks attended the unit and a spokesman for fire services said there were no injuries.
- AAP