Speed factor examined after XPT derailment

A train that crashed north of Melbourne, killing two people, was reportedly speeding before it derailed on a notorious section that had caused trouble for drivers in the past.

Passengers described being thrown violently around inside the train when the Sydney to Melbourne XPT diesel locomotive and five carriages came off tracks near Wallan Station, 60km north of the city on Thursday evening.

The train's driver, a 54-year-old man named by Nine newspapers as Canberra resident John Kennedy, and his pilot, a 49-year-old from Castlemaine in Victoria, died at the scene, while 11 were injured.

The train, carrying about 160 passengers, was reportedly meant to slow to 15km/h to divert through a "passing loop" at Wallan when it was derailed.

But passengers believe it had been moving much faster.

A Sydney man described "hanging on for grim death" as the train came off the tracks.

"It probably went about 150 metres before it stopped, there were carriages going sideways - pretty horrifying," he added.

The man said train staff had handed out complaint cards to passengers moments before the derailment, after lengthy delays caused by ongoing problems with signals on the line.

Passenger Leyon Gray told the ABC the train derailed minutes after taking off again after sitting stationary on the tracks.

"The train got going and we were probably doing 80 or 90km/h.

"Next thing we were thrown out of our seats."

The train, which had left Central Station in Sydney at 7.40am, had been due to arrive at Southern Cross Station in Melbourne at 6.30pm.

There were 160 passengers and crew on board the train, which was running more than an hour behind schedule when it derailed just before 7.45pm.

Police are amazed more passengers weren't hurt.

Some passengers claimed they heard an onboard announcement saying the driver was trying to make up for a lost time before the crash, but police would not confirm this.

The rail union and Victorian National deputy leader Steph Ryan said safety concerns about the track have been raised for some time.

"(The derailment) occurred over a section of track over which was awaiting maintenance," Rail, Tram and Bus Union secretary Luba Grigorovitch said in a statement.

"Conditions were altered and V/Line drivers rightly refused to traverse this section over the past week."

Ms Ryan said she raised concerns about the line with Victoria's Public Transport Minister as recently as Tuesday in parliament after another train derailed further up the line in January.

But Deputy Prime Minister Michael McCormack said he was not aware of complaints by drivers about the safety of the section of the track

"No authority would let passengers travel on unsafe track," he said at the scene.

"We will ensure that proper answers are found for the bereaved families and making sure these sorts of things don't happen again."

Asked about the claims, the Australian Rail Track Corporation (ARTC) replied that as the investigation is under way, it was unable to provide comment on specific details.

Australian Transport Safety Bureau commissioner Greg Hood said a preliminary investigation would be conducted within 30 days.

Investigators will look at several factors, including speed.

The section of the track where the crash happened was commonwealth-owned.

The ARTC is in charge of rail maintenance, while the train is managed by Transport for NSW.

Police said it will take days to clear the tracks, with buses set to replace all Seymour, Shepparton and Albury train services until further notice.