Police say they are perplexed by a stabbing outside a police station in Melbourne's south-east, after two drivers followed each other across the city in a road rage pursuit.

Key points: One man was stabbed in the arm and leg and the other suffered facial injuries

One man was stabbed in the arm and leg and the other suffered facial injuries The men had followed each other for nearly 40 kilometres across the city after a "road rage incident"

The men had followed each other for nearly 40 kilometres across the city after a "road rage incident" Police are calling for witnesses to an alleged crash between the two in the Burnley Tunnel

Two men, aged 54 and 27 and both from Berwick, were driving along the Tullamarine Freeway when a "road rage incident" occurred about 8:00pm yesterday, police said.

The 54-year-old was driving a silver Volkswagen Golf, while the 27-year-old was driving a white Nissan Navara, with his partner and young child inside.

The two drivers then followed each other from Essendon in the city's west, to the Glen Waverley police station in the south-east, nearly 40 kilometres away.

After arriving at the police station the two men got out of their cars and a fight broke out.

"A physical altercation ensued which resulted in the 27-year-old being stabbed in the forearm and leg and the 54-year-old suffering facial injuries," Victoria Police said in a statement.

"Both men were taken to hospital with non-life-threatening injuries."

The left-hand-side mirror had been smashed off the silver Volkswagen Golf. ( ABC News )

Victoria Police Sergeant Janine Saunders said it was an example of road rage unlike any she had ever seen.

"Obviously there are road rages, but not over [a] 30 kilometre distance, over about six suburbs to end up here in a fist fight and a stabbing out the front of a police station," she said.

"That's what we're a bit perplexed about as to how you can keep that anger going for 30 kilometres to end up in a fist fight out the front of a police station."

Sergeant Saunders said the men claimed one cut the other off in Essendon, and one of the cars side swiped the other in the Burnley Tunnel.

"They were not known to each other, just two random people on the freeway," she said.

"They're basically blaming each other, that's all I can say at this stage.

"At this stage both parties are victims and both parties are possible suspects."

Sergeant Saunders said the older driver called triple zero and was followed to the Glen Waverley police station by the younger man.

"The CCTV footage is being viewed by the detectives and both parties will have to be formally spoken to at some stage.

"We've located a weapon and that's in our custody. We're not a hundred per cent sure how it's been produced or at what stage it's been produced and those enquiries are ongoing."

A tent was set up at the crime scene last night to protect evidence from rain, as police officers collected evidence and photographed the two cars.

Blood could be seen on the ground near the cars.

Investigators have appealed for anyone who saw the cars on the Tullamarine or Monash freeways or in the Burnley Tunnel to contact police.

"We just ask people to control their emotions in road rage incidents, it's safer to walk away," Sergeant Saunders said.

"Take a deep breath, calm down and drive away and if the other party doesn't, attend a local police station."