An innocent family has been forced to flee their home in Victoria’s west after they were targeted by an arsonist as payback for helping police.

A father and his two children, the youngest just five years old, were inside their Cobden home when a firebug torched the property.

“The family was petrified. They managed to race out of the back door,” Detective Senior Sergeant Chris Asenjo from Warrnambool Police said.

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Police say the family was targeted for simply helping with another investigation in their street.

“This fire was lit as retribution,” Det. Snr Sgt Asenjo said.

“Detectives say this firebombing was not only brazen. It’s an absolute disregard for human life and it put these people at real risk of serious injury or death.”

The traumatised family has not returned to their home since the attack eight months ago.

“Such significant trauma that they haven’t returned to their house,” Det. Snr Sgt Asenjo said.

7NEWS understands the family gave police information about the shooting of a woman on their street.

A 26-year-old man was arrested over that crime.

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The arsonist remains on the run, but police have finally released crucial evidence.

“The house was fully engulfed. So we’ve had some real trouble in obtaining the footage,” Det. Snr Sgt Asenjo said.

CCTV footage shows a Mazda 3 travelling at speed towards Camperdown just minutes after the fire.

Investigators believe the arsonist had help.

“A group of people in the Cobden, Camperdown, Timboon area that have come together to ensure this fire’s been lit,” Det. Snr Sgt Asenjo said.

“A member of the public will know who this person is.”