MARTY Smith's car exploded on the way to work on Thursday after a gas leak hours earlier in his neighbourhood.
The freak accident, which stunned seasoned police and firefighters, left the father of four in a Brisbane hospital with serious burns to his face, arms and body.
Mr Smith's car was parked on a Bridge St footpath on Wednesday night and steadily filled with gas from a leak in an underground pipe.
As the father of four drove to work, his car began to ventilate, increasing the combustibility of the gas inside.
He was two blocks from home just after 7am on Thursday when he lit a cigarette sparking the explosion at the corner of Bridge and Hume Sts. The force of the blast blew out the front and back windscreen and warped the car doors.
City Patrol Group Inspector Stephen Angus described it as "bizarre".
"It's one of the most freakish things I've ever heard," he said.
The cause of the explosion baffled emergency services at the scene, who initially suggested a faulty LPG line inside the car could be to blame.
"We were running instruments over the car to see if there had been an accelerate in the car, but we found nothing," Queensland Fire and Emergency Services Inspector Peter Bradow said.
"It had us baffled."
Forensic police were unable to determine the cause after a mechanical inspection on Thursday.
It was only when a neighbourhood gas leak was reported to authorities about 4.45pm on Thursday the bizarre puzzle pieces began to fall into place.
Insp. Bradow said a Bridge St resident in East Toowoomba reported shimmering gas waves and a strong smell of natural gas from the underground line.
Insp. Bradow recognised the address as near that of the man seriously injured that morning after the explosion, and tyre marks suggested the car had been parked on the footpath on a regular basis.
"As I had attended that morning, I knew the address of that person was the same address," he said.
"These gas lines, from time to time due to ground movement, can fracture."
Homes were evacuated because of readings of 99 per cent pure gas at the leak site.
Readings of 40% gas were reported up to five metres away. QFES deems a reading of 12% safe.
The exclusion zone was lifted by 9pm after gas contractors repaired the leak, but the circumstances surrounding the incident baffled police and QFES.
"I don't know how he survived," Insp. Angus said.
"It is a truly bizarre and unfortunate thing."
Insp. Bradow said he had never encountered a similar situation in more than 20 years as a firefighter.
"To turn up and see the doors pushed out like that, and the car so damaged, it's incredible he's still alive."
Allgas Energy, part of the APA Group, owns the underground gas distribution network in Toowoomba. APA Group said in a statement: "This is a Queensland Fire and Emergency Services and Queensland Police investigation."
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