The early morning train from Warrnambool to Melbourne was cancelled on Friday after carriages detached from a locomotive.
A V/Line spokeswoman confirmed the 6.06am train service was axed following a train fault, which happened soon after departure from the Warrnambool station.
A total of five passengers were held onboard the service to Melbourne while arrangements were made to move the train back to the Warrnambool station platform where they could safely disembark.
Alternative travel arrangements were made for the passengers, involving a replacement bus.
The train fault will result in further changes to services on the line on Friday - including the cancellation of the 7.30am Melbourne to Warrnambool service and 12.07pm Warrnambool to Melbourne run.
A V/Line spokeswoman apologised for any inconvenience.
"We thank passengers travelling on the 6.06am Warrnambool to Southern Cross Station service this morning for their patience after a train fault led to delays, and sincerely apologise for the inconvenience caused," she said.
"As always the safety of our passengers and staff is our number one priority and passengers remained on board the service until it returned back to the platform at Warrnambool station where they could safely disembark.
"The locomotive will be thoroughly inspected to determine the cause of the fault and ensure any required repairs are made before it returns to service as per our standard procedure."
Passengers are urged to visit the website or download the V/Line app to monitor any service impacts and plan their journey.
V/Line's performance policy means compensation may be available to customers who experience a delay of 60-minutes or more in a single journey.
To find out more or apply for compensation passengers can contact 1800 800 007 or visit the V/Line website (vline.com.au).
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