Police and emergency services responded to reports of collision between three trucks in Gerang Gerung this morning.

Investigators have been told the collision occurred on the Western Highway shortly after 1am this morning.

One of the trucks rolled off the road and came to rest in paddocks nearby.

The driver of the truck has been airlifted to hospital with life-threatening injuries.

A second driver has been transported by road to hospital with non-life-threatening injuries.

The third driver was taken to hospital for observations.

It is expected that the Western Highway will remain closed for some time while investigators remain on the scene.

The exact cause of the collision is yet to be established and the investigation remains ongoing.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report at www.crimestoppersvic.com.au

UPDATE: The Western Highway, Gerang Gerung is closed in both directions between Dimboola and Nhill following a serious collision.

Adelaide bound motorists should follow the detours from Dimboola to Jeparit, and then on to Nhill.

Melbourne bound vehicles should detour from Nhill to Jeparit, and then through to Dimboola.

All motorists are urged to allow extra time for their journeys.

The closure is under the control of emergency services. The Western Highway will open as soon as it is safe to do so.

Real-time traffic conditions are available at traffic.vicroads.vic.gov.au or via the VicTraffic mobile app. The latest public transport information and network status is available at ptv.vic.gov.au or in the PTV mobile app.