Daughter warns her dad's killers: 'we know who you are'

The grieving daughter of a man killed in an arson attack has warned her dad's murderers that "you better hand yourself in now because we've got a good idea who you are".

Father-of-three, Hai, aged 42, and another man, 48, were found dead in apartments at a converted factory in Sunshine North, Melbourne, after an arsonist lit a fire at a nearby panel shop on February 23.

Police believe the attack on the panel shop was targeted but it then spread to the area where the men were sleeping.

Hai's 18-year-old daughter, Jade, fronted a police media conference on Friday where she described the attack as "shocking", saying her family needed closure.

"(Dad) was under the assumption it was safe to stay there and, he had his challenges, but he was a good person, he was pretty funny, he loved to joke around," she said.

"It's such a horrible thing to do. Was it really worth whatever you wanted?"

Police believe the attack on the panel shop was targeted and have released footage of a white dual cab ute with a silver tray used in the incident.

A car pulled up outside the business before a man jumped out, emptied the contents of a jerry can on the floor, set it alight and fled.

The ute was later found burnt out about 50km away in Coimadai.

Burnt out car following a panel shop fire
The vehicle used in the arson attack was found burnt out about 50km from the crime scene. (HANDOUT/VICTORIA POLICE)

Jade said the circumstances of her father's death were confusing and it had been a lot for his three children to come to terms with.

Victoria Police Detective Acting Inspector Tracy Johnston urged anyone with information about what happened to come forward to ensure someone was held to account for the deaths.

"It is an incredibly, incredibly tragic incident. Two men innocently sleeping have lost their lives as a result of this reckless and abhorrent criminal behaviour," she said.

The two men were much-loved by their grieving families, who are still searching for answers more than four months on from their deaths, Det Insp Johnston said.

People who were in the area at the time or have dashcam footage have been urged to contact investigators.