There were scenes of utter chaos and devastation in Springvale on Friday, after a man doused his body in accelerant and set himself on fire in a crowded bank just before lunchtime, sparking an explosion that injured dozens.
Paramedics said 27 people were injured - six of them critically - inside the Commonwealth Bank on Springvale Road, about 11:30am.
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CCTV shows alleged arsonist moments before Springvale bank fire
Retrieving the accelerant he would use to set himself alight, CCTV from a local cafe shows the alleged arsonist moments before he entered the Springvale Commonwealth Bank and injured 27 people. Vision courtesy Seven News, Melbourne.
Amateur footage taken by a witness and posted to Facebook showed dazed-looking people sitting on the footpath after the explosion, one woman weeping and moaning in pain, as witnesses poured water over people's injuries.
One toddler screamed in panic and pain, his hair and face blackened, as his sobbing mother tried to sponge his face clean.
Fire crews arrived at the bank within 90 seconds of the explosion.
The man believed responsible for the horrific attack, understood to be 21, was under police guard at The Alfred hospital on Friday night, where he was being treated for his injuries.
Late on Friday, CCTV footage emerged of a man picking up a large plastic container outside local cafe Asmara, and walking towards a nearby Caltex service station.
The footage showed the man again at 11:22am, walking back past the camera in the direction of the bank. A short time later, an explosion was heard.
After the fire, the badly-burnt man fled into a laneway at the back of the bank, where he stood with his head in his hands as he was intercepted by paramedics and police, Greater Dandenong Acting Inspector Jacqui Poida said.
She said it was too early to say what the man's motive was, and urged anyone who witnessed the attack to call police or Crime Stoppers.
The youngest of the man's victims was a toddler. The oldest were in their 70s and 80s.
Ambulance Victoria group manager Andy Roughton said six people were in a critical state. Asked whether any could succumb to their injuries, he said: "I hope that's not the case but there's a chance."
By Friday evening, three of the six critically-injured people had improved enough to be listed as stable. One other was listed as serious, but stable.
Paramedics treated 27 people at the scene for burns and smoke inhalation. Commonwealth Bank staff were among the injured.
Paul Carrigg, operations manager of Dandenong CFA, said the man had used a liquid accelerant to spark the explosion.
"There would have been a lot of flames to start with, and a lot of smoke," he said.
Smoke poured out of the building as witnesses raced to the scene.
One witnesses, Ernie Gonzalez, told Fairfax Media he had heard another witness say a man had set himself on fire at the entrance of the bank before running inside and squirting gasoline on the carpet.
"He's setting the carpet on fire as he's running towards the back of the bank," Mr Gonzalez said, adding that the bank tellers had been forced to run through the flames to escape the building.
"I could see flames in the entrance and I could see people running out covered in charcoal - they were black," he said.
He said after he saw people run from the bank, he went to a lane behind it, where he saw a man in his 20s crouched behind some boxes.
"He was wearing tracksuit pants that were burnt, they looked like shorts," he said.
"His skin was falling off his legs."
Mr Gonzalez said he saw police surround the man before he was arrested and taken to hospital by paramedics.
Anthony Banh, the manager of Love Central Jewellery across the road from the bank, said he went outside immediately after people came running and screaming past his the shop.
"A guy had severe burns on his face and arms and everything. There was another man crouched on the ground with severe burns."
Mr Bahn said people came running to help the injured and to use fire hydrants to put out the flames.
"People were quite brave," he said.
Commonwealth Bank chief executive Ian Narev issued a statement saying management was "deeply concerned" about the Springvale attack.
"Our absolute priority is the welfare of our customers and staff who were in the branch at the time," he said.
"We have teams assisting our people and a customer liaison officer available for affected customers, and will keep them engaged as long as is necessary. We thank the emergency authorities for their quick response and actions."
The Arson Squad is investigating.