Police are offering a $500,000 reward for any information about a house fire linked to Melbourne’s tobacco wars that killed an innocent young woman earlier this year.

Katie Tangey, 27, was house-sitting for her brother in Truganina when the property was set alight in the early hours of January 16.

Tangey called triple-0 saying she was trapped inside the home but by the time help arrived, it was too late.

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The family’s dog, a golden retriever named Sonny, also died in the blaze.

Police believe Tangey was the first innocent victim in Melbourne’s ongoing illicit tobacco dispute.

The arson attack is believed to have been targeted but the offenders got the wrong address.

It’s been six months since the tragedy and police have not made any arrests.

In April, investigators released a digital composite image of a man who they believe was seen on a security camera at the home just before it was engulfed in flames.

The man was wearing an orange hoodie and holding what appeared to be a jerrycan moments before an explosion.

Another man was also captured on the security camera. The pair fled the scene.

A dark-coloured car — similar to a BMW X3 or X5 — was seen on CCTV parked outside the home on Dover St just before the fire.

Two people were seen getting out of the car.

The dark-coloured vehicle was then captured on CCTV travelling north on Forsyth Rd in Truganina not long after.

Police executed a search warrant at a home in Dandenong on June 12 and seized a number of phones which are undergoing forensic analysis.

An anonymous phone call was also made to Crime Stoppers where a name, believed to be a pseudonym or nickname, was given to police.

“Investigators are still urging this particular caller to make further contact and provide additional information,” police said.

Police are now offering up a $500,000 reward for any information leading to the arrest and conviction of the person or people responsible for Tangey’s death.

Detective Inspector Chris Murray said investigators believe they know who directed the arson attack and are close to proving who actually carried out the crime on the night.

“Those responsible for Katie’s death know they targeted the wrong house and they have to live with the knowledge that they are responsible for the horrific death of a completely innocent young woman,” he said.

“$500k is a lot of money – hopefully it will encourage those people out there who do know something to do the right thing and come forward. Katie’s family deserve answers.”

He said the investigation remains a priority for police.

“These people need to be held accountable for the fact they committed a crime which ultimately led to the death of a young woman who had her whole life ahead of her.”

Anyone with any information has been urged to contact Crime Stoppers.