Emergency services were called to the highway at Alpine, near Colo Vale, about 12.30pm on Sunday following reports of a multi-vehicle crash.

Officers from the Hume Police District found the driver of one vehicle, a man, suffering serious pelvic and leg injuries.

A man driving a second vehicle and a female passenger, both believed to be aged in their 20s, suffered serious fractures and abdominal injuries.

All three were taken to Liverpool Hospital in a serious condition.

The driver of a third vehicle, a 37-year-old woman, was treated for shock and taken to Bowral Hospital.

Officers from Crash Investigation Unit established a crime scene and are investigating.

All northbound lanes have now reopened.

Traffic remains heavy so drivers have been told to allow plenty of travel time until conditions return to normal.

1.40pm: A multiple-vehicle crash at Colo Vale has closed the Hume Highway in a northbound direction.

Diversions are in place via the Old Hume Highway at Welby.

Emergency services and RMS are currently at the scene.

Motorists are advised to reduce speed and exercise caution.

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