Police are investigating whether a man charged with making threats to kill during a road rage incident is linked to the ongoing violence in Melbourne's north.

There have been a series of drive-by shootings in Glenroy, Jacarna and Coolooroo over the past nine days.
Now police have admitted they have concerns for public safety in Melbourne's north-western suburbs.
Police say two rival families battling for control of the local drug trade are responsible for the violence.
Police have been doorknocking homes and stopping cars in the area.
On Wednesday a man was pulled over in nearby Coburg after he threatened two people with a fake gun in a road rage incident.
Assistant Commissioner Graham Ashton says they are investigating whether the man is linked to the recent violence.
"The firearm was an imitation one, It was used in an incident earlier this morning where he threatened two other civilians and he's been charged with making threats to kill, threats to inflict serious injury and assault charges," he said.
Police say they do not expect to make any immediate arrests over the recent shootings.
Assistant Commissioner Ashton says the two families believed to be at the centre of the violence are not cooperating.
"We are not tolerant in any way to this sort of behaviour, and the sort of people that are out there conducting themselves in this way need to get the continued strong message from Victoria

 

Police that it is not being tolerated," he said.
The head of one of the families who was the target of an attack accused police not doing enough to protect his family.
Assistant Commissioner Ashton says Santiago Taskforce, which investigates crime gangs of Middle Eastern origin, is now involved.
"Santiago, at the moment, is focussing on the families, is focusing on the investigation," he said.
"It's painstaking work, because you need evidence to act in relation to these things.
"We've got to make sure the evidence Santiago gets holds up in court, and so solid arrests can be made, and so that work's ongoing."
Victorian Premier Ted Baillieu says he is confident police are making progress.
"We've sought - sought and been given - assurances that additional resources are being provided, and I understand that's the case," he said.
"I'm not in a position to get into any of the operational details, but we've been assured that progress is being made."