A section of the South Coast rail line at Kembla Grange will be closed for days after a train derailed.
At around 4am on Wednesday, a northbound train hit a van parked on the tracks at the West Dapto Road rail crossing at Kembla Grange.
Police have said the car, believed stolen from a home in Flinders hours earlier, had been driven 50 metres along the tracks from the level crossing.
The train driver and three of the passengers on board were taken to hospital with minor injuries.
A Transport for NSW spokeswoman said they were assisting police in the investigation of the incident.
It is expected this incident will cause delays for the remainder of the week for travel between Wollongong and Kiama as repairs take place to damaged infrastructure.— NSW TrainLink South (@TrainLinkSouth) October 20, 2021
If you must travel please allow plenty of extra travel time and check transport apps for service updates. pic.twitter.com/KUQmwTTdWU
The spokeswoman said the derailment caused "substantial damage to the overhead wiring, signalling, and associated infrastructure" that will take days to repair.
"The section of line is expected to be closed for several days while repair work is carried out and the damaged train is salvaged," the spokeswoman said.
While this section of track is closed for repairs, buses will replace trains between Albion Park and Wollongong in both directions, and a shuttle train service will operate between Albion Park and Kiama.
Customers will need to change trains at Wollongong or Albion Park.
The accident made an already disrupted day worse for Illawarra commuters, happening on the same day rail workers went on strike over a new pay deal.
On the South Coast line Wednesday's services were already running to a weekend timetable and buses were assisting trains between Wollongong and Thirroul.
Buses were replacing trains between Port Kembla and Wollongong.
Alex Claassens, the NSW secretary of the Rail Tram and Bus Union - the union that called the strike - said they were working with management to ensure everything possible is done to support affected commuters.
"It would have been a horrific thing for anyone to go through," Mr Claassens said of the derailment.
"Incidents like this highlight just how tough a job working on our trains can be."