A truck driver has reportedly been thrown from his cabin in a shocking crash on the Western Freeway north-west of Melbourne.

The collision happened shortly before 8am on Friday, at Darley, near Bacchus Marsh.

One of the trucks has burst into flames.

One driver has serious head injuries and a second driver has non-life-threatening injuries.

Channel 7 cameraman Bryce Holloway was about a kilometre behind the trucks when they crashed.

He described the scene to Neil Mitchell.

“If you can imagine a bomb going off, it looked like that,” he said.

“I saw a big plume of smoke go up, it was carnage.

“There’s debris everywhere.”

CFA local district operations Chris Bighan said it’s lucky both drivers weren’t killed.

The cause of the crash is not yet known.

The freeway is expected to be closed for hours.

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