Road Rage Attacker Who Stabbed Man In Front Of Wife And Child Wanted By Police

Police are appealing for witnesses to a road rage stabbing incident in Sydney's west which left another man requiring emergency surgery.

Police have described a violent road rage fight on the busy M7 motorway as "alarming", after one man was left with deep stab wound to his stomach and the other fled the scene.

"It appears to be completely random at this stage, but bear in mind we have only spoken to one party at this stage they would indicate it’s a random incident," NSW Police Acting Inspector Steve Vuletas said.

Around 4.30pm on Friday afternoon, a 42-year-old man was driving along Richmond Road at Glendenning with his wife and daughter on board their Toyota Hilux.

According to police, the family became involved in what they say began as a minor road rage incident with a man in an orange Toyota Corolla.

"From what police can conclude the incident was sparked by a minor driving matter," Vuletas said.

The man in the Corolla threw an unidentified object at the Hilux as both cars entered the on-ramp to the M7.

A short time later, right in the middle of the busy M7 motorway, both cars stopped and the men confronted each other.

The man in the Corolla produced a knife, stabbing the 42-year-old father in the stomach, before speeding off in a southerly direction.

Police say they are still looking for the driver of the Corolla who has been described as Mediterranean/Middle Eastern appearance, about 20 years old, chubby build, short in height, and seen wearing a hi-vis shirt.

"I certainly encourage him to come forward and help assist us with whatever occurred yesterday," Vuletas said.

Following the incident the victim attempted to drive himself to nearby Blacktown Hospital, while his wife called Triple Zero.

The operator advised the man to pull over which he did, they stopped on Bungarribee Road, Doonside, until the arrival of an ambulance.

He was taken to Westmead Hospital for emergency surgery last night and is now understood to be in a stable condition.

Police are appealing for any witnesses, or anyone who may have dashcam vision that may depict the incident, or the offender's vehicle, to come forward.

With AAP.