Dramatic CCTV footage has captured the moment a man became engulfed in flames, seconds after allegedly torching a western suburbs tobacco shop.

Just before 3am, two men dressed in dark clothing and hoodies pull up outside The Boss tobacco shop in Melton in a white ute, before ramming through the roller shutters.

Moments later, the pair gets out and begins dousing the inside of the High St business with petrol from jerry cans.

Then, in shocking scenes, the two men set the shop alight, only to accidentally set themselves on fire.

One man can be seen running with flames licking up his foot, while his accomplice becomes completely engulfed before rolling around on the ground desperately trying to put out the flames.

The man, in his 20s, continues rolling on the ground as his accomplice jumps back into the ute and speeds away.

The badly injured man was found just outside the tobacco shop and airlifted to The Alfred hospital, where he remains in a critical condition.

On Thursday morning charred remnants of clothing were found outside the shop, including a burnt puffer jacket, a shoe and a cap.

Shortly after 3am, police received reports of a vehicle on fire on the Western Highway in Hopetoun Park, which detectives believe was the white Ute used in the ram raid and firebombing.

The car has been seized for forensic testing.

Police are still trying to identify and locate the other accomplice, who is believed to have significant burns to his hands and feet.

Detective Inspector Chris Murray from the Arson and Explosives Squad said the man was in a critical condition and could die from his injuries.

“We have said repeatedly that deliberately lighting fires comes with immense risk, not only to the broader community but also to the offenders involved,” said Inspector Murray.

“We have also seen incidents where offenders have died as a result of sustaining burns and this remains a very real possibility to happen again with this incident.”

Inspector Murray said the force was thankful an innocent member of the public was not the one caught up in the blaze.

“Fire is uncontrollable and unpredictable and we can only be thankful it’s not an innocent member of the public who has been injured.

“If there is anyone out there who witnessed the fire or has any information at all about who is responsible, then I urge those people to come forward and tell us before this happens again with potentially fatal consequences.”

Police have released CCTV footage and an image of the incident.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or online at www.crimestoppersvic.com.au.