PEAK-hour train services travelling through Berwick were thrown into disarray when a truck collided with a train at Pakenham on Tuesday.
Hundreds of commuters were unable to get to Hallam, Narre Warren and Berwick train stations until buses arrived and completed their journey.
The delay was caused when a truck transporting crushed rock crashed through a boom gate along Cardinia Road and collided with a Melbourne-bound train about 3.40 pm.
The west-bound train was damaged, but the 10 or so passengers on board, although badly shaken, were not injured, police said.
The truck driver, a 29-year-old Morwell man, was treated for shock at Casey Hospital but later discharged.
The front of the truck was almost destroyed.
Connex spokeswoman Kate De Clerq said the collision caused inconvenience to peak-hour commuters, with no trains running between Pakenham and Dandenong stations for almost five hours.
Victoria Police, Connex, the Transport Safety Bureau and other authorities are investigating the crash.
Police said a potential catastrophe was averted by seconds.
Almost 200 passengers, including school children, were on a Pakenham-bound train that was pulled up about 500 metres from the crash scene.
Police have appealed for witnesses to contact Senior Constable Brad Cummins at Cardinia Traffic Management Unit on 5941 1033.