Police are in attendance at a serious crash on the Northern Motorway, State Highway 1, near the Onewa Road off-ramp.

The crash, between a van and a truck, has occurred at around 3.30pm in south-bound lanes just after the off-ramp.

The van driver has sustained critical injuries.

Emergency services are currently at the scene and the Serious Crash Unit has been advised.

All three south-bound lanes are currently closed near the crash site.

Traffic is being diverted off the motorway at the Onewa Road off-ramp, to rejoin State Highway 1 via the Onewa Road on-ramp.

Please expect delays on your commute this afternoon.

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