A good, hard-working family has been the target of five shooting incidents in the past seven months, police say.
Shots have been fired at homes in Thomastown and Mill Park as well as a Campbellfield business linked to the same family.
On one occasion last December, a stranger knocked at the door of the Thomastown home just before midnight, identified himself as John and fired a shot that narrowly missed the male resident.
The victim's wife and three children were asleep in the house at the time.
Detective Senior Constable Matthew McKenzie said it was not clear why the family, who have no organised crime links, were being targeted.
"We do not believe in any way that these are random attacks," he told reporters on Sunday.
"I will make this clear that this family is a good family, a hard-working family that have had no contact with police other than being the victims of these crimes."
The last shooting happened in February, when a number of shots were fired at the Thomastown house.
Police have released CCTV footage of the gunman, who fled in a white Nissan Navara with black roll bars.
Det Snr Const McKenzie said at least one other offender was involved in the other incidents.
