A truck driver has died after two B-double trucks collided on the Hume Highway near Gunning this morning, with motorists warned to expect significant traffic delays.

Emergency services were called to the northbound lanes near Collector Road about 6am on Friday after one B-double truck crashed into the rear of another.

The driver of the rear truck died at the scene.

The other driver was uninjured and was taken to hospital for mandatory testing.

Police have established a crime scene and are investigating the cause of the crash.

Motorists are urged to avoid the area as significant delays are expected.

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