A driver is fighting for their life following an afternoon crash that brought down a power pole and caused diesel to leak across lanes.

All outbound lanes of the Monash Fwy in Melbourne’s southeast have been shut between Warrigal Rd in Chadstone and Foster Rd in Mount Waverley by the incident on Wednesday afternoon.

WATCH THE VIDEO ABOVE: Major crash closes Monash freeway in Melbourne.

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A four-kilometre stretch of the major freeway has been closed as a result, setting up a slow journey home for thousands of motorists.

An emergency response was sparked when a truck crashed into a concrete median divider near Huntingdale Rd about 2.20pm.

“The driver was transported to (The Alfred) in a critical condition,” Victoria Police said.

Three other cars were hit by the truck when it blew a tyre, 7NEWS reports.

Fire Rescue Victoria said they arrived within six minutes of a Triple-0 call to find the truck smoking and leaking fuel.

“A light pole was also downed with debris thrown onto inbound lanes,” an FRV spokesperson said.

“Firefighters contained a significant spill of diesel.”

Drivers are being re-directed off the freeway at Warrigal Rd, with significant delays stretching back to Toorak Rd.

Authorities say traffic is “still building”.

“Motorists should exit the outbound lanes of the Monash Freeway as early as possible and head for Dandenong Rd,” Victoria’s Department of Transports and Planning said in an alert.

“This closure is under the control of emergency services, and lanes will open as soon as it is safe to do so.”

Anyone with information should contact Crime Stoppers on 1800 333 000 or make a report online.