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Police in Australia are still unsure what caused a massive explosion that destroyed a takeaway shop in Sydney early this morning.
A man is fighting for his life in hospital after being critically injured in the blast, which forced hundreds to be evacuated from nearby homes.
Emergency crews were called to Mountain St in inner-city Ultimo in the early hours of the morning, following reports of an explosion loud enough to be heard several kilometres away.
The blast, which occured at 1.20am (3.20am NZST), destroyed Nando's chicken takeaway shop and ripped through apartments in the nine-storey building.
The critically injured man suffered serious burns in the explosion and was rushed to Concord Hospital, where he remains in a serious but stable position.
He has been linked to a car, found parked near the building, which has been seized by police investigating the explosion and subsequent fire.
The man was not a resident of the Quadrant apartment block or a worker at the Nando's business, police Acting Commander Chris Keen told reporters.
"The person who was seriously injured, he was in the lift well beside the chicken shop," he said.
Police told the Sydney Morning Herald that gas and electricity sources in the wreckage of the building were being examined.
Detectives are also trying to establish whether a robbery at Nando's at 9.30pm (11.30pm NZST) last night had any connection to the explosion.
"Two males, one armed with a knife, assaulted the attendant and escaped with a sum of cash," police said in a statement.
"Inquiries are continuing. It is too early in the investigation to link the two incidents."
A second man was rescued from the second floor of the building and taken to Royal Prince Alfred Hospital in a stable condition.
Triple-0 callers reporting the explosion said there was a strong smell of gas, but Commander Keen said that smell was not noticed by firefighters who were first on the scene.
Staff from gas company Alinta are assisting police and NSW Fire Brigades with their investigation, spokesman Peter Wood told the SMH.
The Nando's business, closed at the time of the explosion, was completely gutted and nearby offices also sustained damage.
Several hundred people were evacuated from Quadrant apartments, with two busloads taken to emergency accommodation at a hotel near Sydney Airport.
It may be days before residents - many of whom are university students - and workers in the area can return to their properties.
"This may be a crime scene for a number of days at this stage," Commander Keen said.
A resident named only as Glen told ABC radio the noise of the blast was terrifying.
"It was really scary," he said.
"I was awake and felt something and it was that loud, I jumped on the floor."
The blast blew plate glass doors off hinges and engineers have been called in to assess the structural stability of the building.
Police are yet to speak with either of the injured men.
- AAP, NZ HERALD STAFF
