A multi-car collision inside Northbridge tunnel has caused a traffic nightmare on Wednesday afternoon.
Traffic is banked up heavy on approach eastbound towards the tunnel, following the devastating crash that was reported about 2.40pm by Main Roads.
A passerby reported at least five cars had been caught up in the wreckage, some with extensive damage.
Emergency services confirmed that several vehicles were caught up in the crash, but said no one was harmed or trapped.
Police are attending the scene.
The crash has since been cleared and traffic remains heavy on approach.
The left lane was blocked off.
Motorists are advised to drive with caution as peak hour fast approaches.
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