Police say the occupants of an Eaglehawk unit destroyed by petrol bombs are extremely lucky not to have been seriously injured or killed.
Detective Leading Senior Constable Andrew Heazlewood, of Bendigo Crime Investigation Unit, said the Molotov cocktails hit the lounge room.
Two people were believed to be in the room at the time. Police believed the third occupant was in the bedroom.
"The fire spread quite quickly inside," the detective said.
He said the unit was "totally destroyed" by the fire.
However, none of the occupants were injured.
"It is an incident that could have resulted in very serious injury or death," Detective Leading Senior Constable Heazelwood said.
Police believed at least two people were responsible for petrol bombing the property, and at least two Molotov cocktails were thrown.
The motive for the attack had yet to be discovered. However, Detective Leading Senior Constable Heazelwood believed the incident was planned and the offenders "weren't worried about the consequences at all."
"We believe they were prepared to execute that behaviour," the detective said, describing what occurred as a very callous act.
He said the unit's occupants had been assisting police with their inquiries.
"If anyone does have any information, I'd urge them not to hold back," Detective Leading Senior Constable Heazelwood said.
"It might be the vital piece of information we need to prevent them from happening to anyone else."
He urged anyone with information to contact Crime Stoppers on 1800 333 000.
Three people have escaped an Eaglehawk home without injury after Molotov cocktails were thrown through the front window.
Police believe two bottles containing an accelerant were thrown at the Red Hill Court home about 3.30am on Thursday, October 8.
Three people were asleep inside but escaped after the noise awoke them.
The front area of the home was engulfed in flames, but the fire was extinguished by firefighters.
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Bendigo Crime Investigation Unit detectives are looking into the incident.
They believe at least two people attended the address in a vehicle.
Anyone who witnessed suspicious activity or has information on the attack is urged to contact Crime Stoppers on 1800 333 000.
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