Three neighbouring houses in Thomastown were attacked with Molotov cocktails in the early hours on Friday.
Emergency services were called to Victoria Drive, Thomastown, about 3am.
No one was injured during the attacks.
Sergeant Kris Hamilton said detectives were investigating and a crime scene guard would remain in place until the premises could be forensically examined.
“Thankfully property damage was minimal considering the potential,” Sergeant Hamilton said.
He said detectives had so far established the first house had a device thrown at the front bedroom window that smashed. The curtains and the carpet were burnt but thankfully no one was in the bedroom at the time.
A smoke alarm alerted the residents to the fire.
The second house was relatively unharmed after the attack aside from some burnt conifer plants. The third house had smoke damage.
Police are urging anyone with information to contact Crime Stoppers on 1800 333 000 or www.crimestoppersvic.com.au
