A train driver and two passengers have been taken to hospital after a train derailed at Kembla Grange early Wednesday morning.
Emergency services were called to the train line on West Dapto Road just after 4am, after reports of a train and vehicle crash.
Police have been told the four-carriage train struck an unoccupied vehicle that was on the track, before the front carriage of the train rolled onto its side.
Eleven passengers and the train driver were assisted from the carriages, while the driver and three passengers were taken to hospital with minor injuries.
Officers from Lake Illawarra Police District established a crime scene and commenced an investigation early this morning.
According to police, subsequent inquiries have revealed the vehicle was stolen earlier today from a home at Flinders and they're investigating how it came to be abandoned on the train line.
Witnesses have told police a male was seen running from the area soon after.
NSW Ambulance Inspector NSW Ambulance Inspector Norm Rees said emergency services faced a chaotic, and dangerous, scene on arrival.
"The scene was chaotic, it was messy," he said.
"Someone had parked a Nissan Patrol van across the track and abandoned it; the train has hit it and as a result has derailed.
"Subsequently the first carriage has derailed and ended up on the siding, the second carriage has half tilted and the remaining two carriages remained on track.
"It had taken out all the infrastructure - the guard rails, the signals, there was debris all over the place.
"It had torn up part of the track and brought down power lines which were laying across the cabins and station platform - it was a dangerous scene."
Inspector Rees said the train driver was trapped for some time, prior to being released by NSW Ambulance and Fire and Rescue NSW personnel.
"The train driver, aged 39, was transported to hospital with minor abdominal and back pain, and two passengers were also taken to hospital with minor injuries," he said.
An Illawarra Shoalhaven Local Health District spokeswoman said four people were now being treated at Wollongong Hospital for minor injuries - the 39-year-old man plus two other men, aged 64 and 48, and a 53-year-old woman.
The Transport Management Centre has advised that buses are replacing trains between Wollongong and Albion Park on the South Coast Line due to the incident.
Trains will continue to operate between Albion Park and Kiama and between Wollongong and Waterfall.
Passengers may need to change at Wollongong or Albion Park to continue their journey.
Passengers are also advised to allow plenty of extra travel time, listen to announcements and check information displays for service updates.
Anyone who may have information, dashcam footage or CCTV is urged to contact Lake Illawarra Police Station on 4232 5599 or Crime Stoppers on 1800 333 000.
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