A body has been found following a suspicious house fire in Sydney's south-west this morning.
Neighbours reported hearing screams for help after smoke was seen coming from the two-storey home on Montana Way, Macquarie Fields, at 1.35am today.
When Fire and Rescue NSW crews arrived at the scene, the house was well alight.
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While almost everyone in the house was able to escape the fire, a teenage boy was unable to be found.
Once firefighters put the fire out, they went inside the home and found a body in an upstairs bedroom.
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Police set up a crime scene and officers from Campbelltown are investigating.
Anyone with information or dashcam vision from this time is urged to contact Crime Stoppers on 1800 333 000.