A 93-year-old man will be charged over a crash involving a truck on the West Gate Bridge on Friday.

An alert was issued for a BMW Series 7 black sedan with passenger-side damage after its driver smashed into the side of a truck and left the scene about 8.20am before police had arrived.

The aftermath of the crash on West Gate Bridge on Friday. Credit:

The sedan struck the truck in an outbound lane, sending the truck swerving into another lane and into a second truck, which hit the side of the bridge.

The impact caused more than 40 metres of damage to the bridge's safety barrier.