One person has died after a fire was sparked by an explosion at a unit block in inner-west Sydney on Monday morning.
Up to 40 firefighters were on the scene at Young Street, Croydon, just before 6am after receiving reports of a fire in a ground floor apartment.
Fire and Rescue NSW Superintendent Adam Dewberry said several people were trapped on the upper levels of the complex as a fierce blaze burned below.
He said about 30 people were evacuated, while three people were taken to hospital.
Those sent to hospital were one resident who suffered a medical episode, one police officer and one firefighter.
All three were reported to be in a stable condition.
"And, unfortunately, we have had one person [who] has died during the passage of this fire," Superintendent Dewberry said.
A crime scene has been established at the Young Street complex.
The person who died is believed to have lived in the unit where the fire began.
Chief Superintendent Michael Morris said there was evidence of an explosion in that ground-floor apartment.
"Firefighters were confronted with a well-advanced fire and a large field of debris from the explosion," he said.
"They made a rapid attack on the fire and were very successful in quickly knocking down the fire.
"The cause of the fire is under investigation."
Resident Marilena Martelli was getting ready for work when she "felt the house shake".
"And very loud noises, and glass shattering. [I] thought the back of my house was collapsing," she said.
Ms Martelli said she and her family ran out the back and saw a "4-metre tall, big ball of fire" on the ground floor.
"My husband rang (triple-0) and I just went and started knocking on doors and getting people out."
A ladder was used to evacuate residents on the third floor who had been unable to flee the building.
Superintendent Dewberry said 12 fire trucks were on the scene during the "very difficult fire-fighting operation".
"The cause and origin of this fire is being investigated by expert firefighters from our fire investigation and research unit, and we'll be working closely with police," he said.
