An 18-year-old boy has been found dead in his bedroom after a suspicious house fire in Melbourne's northwestern suburbs.
Neighbours were awakened about 1.30am (AEDT) today by the boy's father screaming for help as flames engulfed the Melton South home.
The 58-year-old father and his younger son, aged 13, managed to flee the blaze unharmed but couldn't help the oldest son escape as the flames became too intense.
His body was found in his bedroom after fire crews extinguished the blaze.
Homicide Detective Senior Sergeant Shane O'Connell said the fire was considered suspicious, with damage mainly around the boy's bedroom.
"We're really early days in the investigation and our arson chemists are now here to fully examine the cause of the fire," he said.
No arrests have been made at this time.
He called for calm as tension mounted among family and friends who gathered outside the house.
"Stay calm, let us do our job and hopefully resolve this matter successfully," he said.