Three children have died and a man is in custody after a house fire in Sydney's west overnight.
At least 20 firefighters and six fire trucks rushed to Freeman Street at Lalor Park about 1am today to find the home well alight.
Paramedics treated two boys, aged two and four, at the scene before they were taken to Westmead Hospital in critical condition.
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Both boys died a short time later.
A nine-year-old girl and three boys aged 11, seven and six were treated at the scene before being taken to hospital in stable condition.
After firefighters extinguished the blaze, they located the body of a 10-month old girl.
Police said the three children killed in the blaze are yet to be formally identified.
A 29-year-old woman was transported to hospital for smoke inhalation.
Officers arrested 28-year-old man at the scene and he was taken to hospital under police guard for smoke inhalation.
An investigation is underway into the circumstances behind the blaze, police said.
A report will be prepared for the coroner.
