A man is speaking with police as two young girls and a mother fight for their lives after a suspicious house fire in Melbourne.
Emergency services were called to a two-storey townhouse on Terrigal Street in Chadstone about 9.40pm yesterday.
Firefighters arrived to find flames coming out of the roof and forced their way into the home, where they found three people inside.
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Two primary-school-aged girls and a 37-year-old mother were pulled from the home and resuscitated before they were rushed to hospital.
The children remain critical at the Royal Children's Hospital and the mother is serious at the Alfred Hospital.
A crime scene has been established and an arson chemist is assessing the home.
Police are treating the fire as suspicious.
They are currently questioning a 36-year-old man, who is the fourth occupant of the home, and are not looking for anyone else.
Arson and Explosives Squad Detective Inspector Chris Murray said the man was not at home at the time of the fire and is not currently under arrest.
He added that a gas cylinder is believed to have exploded and started the fire.
"One can only hope and pray that certainly the children get through this, as the mother," he said.
"But we know such an incident where we have an explosion and fire can be absolutely devastating."
According to Fire Rescue Victoria, the blaze involved the bedrooms and ensuite on the second floor.
The fire had penetrated the roof and caused some structural collapse.
The remainder of the house suffered smoke and water damage.
Firefighters brought the fire under control in about 35 minutes.
Anyone who witnessed the fire or has any vision is urged to contact Crime Stoppers.
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