Moment truck jackknifes on bustling highway

Cameras have captured the moment a truck jackknifed on one of Melbourne’s busiest thoroughfares.

Video shows traffic moving steadily along the West Gate Freeway about 7.30am today.

A large truck, travelling in the interior lane, can be seen veering to the left before it dramatically jackknifes, blocking all lanes of the freeway.

The incident caused four lanes to be shut until about 9am, causing major headaches for commuters.

Motorists left trapped behind the crash were warned they'll be there for a while turned off their engines.

It's unclear what caused the truck to crash , with weather conditions perfect in the city this morning.

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