Upper House member Bev McArthur said a passenger was last month forced to leave the train and board a replacement bus service at Sunshine train station, which is located in coronavirus hotspot area Brimbank.

Passengers on the Warrnambool/Geelong line often board V/Line buses when trains are not in use or track works are occurring.

"Travellers who may have planned their journeys to avoid Melbourne hotspots were forced to exit their trains and board buses in Sunshine, an area with the second highest incidence of active cases in all of Victoria," Mrs McArthur said.

"It is utterly shambolic, and deeply worrying."

Mrs McArthur said the bus was also at capacity despite social distancing rules.

"Instead of the required 25 commuters on each bus, these services were crammed full. That is, every single seat was occupied, and people were also standing in the aisles," she said.

"The situation was repeated on succeeding buses, and on my constituent's return journey.

"It is absolutely extraordinary that this has been allowed to happen at a time when COVID cases are beginning to multiply out of control."

Mrs McArthur said Public Transport Victoria told the passenger that train and bus capacity would not be limited because it would "likely cause crowding in other areas such as platforms and stops and enforcement is difficult".

"This is truly breathtaking," she said.

"PTV made no effort to ensure vital social distancing on busy buses, because 'enforcement is difficult'. Little wonder that Victoria's COVID outbreak is spiralling out of control."

V/Line confirmed Warrnambool line passengers travelling on June 27 and 28 changed trains at Geelong and travelled on replacement buses between Sunshine and Southern Cross Station.

The buses also stopped at Footscray to drop off and pick up passengers.

Coaches replaced trains due to works on the Metro Tunnel project

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