A hand grenade has been used to target a notorious family in a troubling escalation of gang violence in Melbourne's north-west.

It is the first time a hand grenade explosion has been investigated in the state's history, Victoria Police believe, underlining the fears of senior officers that underworld figures are increasingly accessing military-grade weapons.

A mother and her infant child were sleeping in a front room of the Tiba family's Lalor house only metres away from the blast on November 19 last year.

The grenade, an M52 manufactured in the former Yugoslavia, is understood to have bounced off the house and detonated between the property and the nature strip.

A front window in the house was shattered and two cars parked on the street were significantly damaged in the explosion. No-one was injured.

The ABC has delayed reporting on the attack at the request of police.

It is unclear how the grenade was brought into Australia, or how many may be in circulation.

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The explosion came as the Tiba clan fought battles on multiple fronts.

An associate of the family, Anwar Teriaki, was gunned down last August in a hit that police suspect was organised by an underworld figure behind bars.

A separate feud between the Tibas and the Comanchero outlaw motorcycle gang marked by jailhouse violence was also behind several shootings in 2016 and last year, police believe.

A computer generated image of a man seen in the area at the time of the explosion. ( Supplied: Victoria Police )

And two members of the family were charged in October with the shooting of organised crime figure Mohammed Oueida six months earlier.

The State Government and senior police believe the recently introduced firearms prohibition orders will quell the spread of illegal guns in the underworld, and could reduce the number of shootings.

The orders are expected to be handed to about 3,000 crime figures, and will allow police to search them, their property, their car, or anybody in their company, without a warrant.

Melbourne's north-west has been plagued by gun violence, with the armed crime squad revealing last year that almost two thirds of all non-fatal shootings in the state occur in the region.

New South Wales police believe a similar order regime introduced in that state four years ago helped reduce shootings.

Detectives from the Echo taskforce will today appeal for more information about the grenade attack on the corner of Yuonga Court and Edgars Road.

They believe a man drove up to the property in a dark-coloured, late 90s to early 2000s Toyota ute about 2:30am.

He threw the grenade at the house before running behind a parked vehicle in Yuonga Court to watch the explosion.

Witnesses said the man who threw the grenade drove a car like this one. ( Supplied: Victoria Police )

He then drove out of the court, before returning to the scene a short time later.

"Investigators believe the attack was targeted and is linked to ongoing feuds between a number of Middle Eastern organised crime groups," a police spokeswoman said.

"A number of people came out on to the street after the explosion and it's believed the offender stayed at the location for some time before leaving in his vehicle."

This van was damaged in the explosion. ( Supplied )

It is not the only reference made by police this month to military-grade weaponry, with a court hearing that Comancheros used a high-powered AK47 or SKS rifle in a drive-by shooting targeting a businessman.

Police pushed for new laws targeting drive-by shootings after tragedies such as the death of Rachad Adra, who was killed and his four-year-old son injured when a similar high-powered weapon was fired into their home in 2015. Mr Adra was not the intended target.

Anyone with information about the grenade attack is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online.