A rail worker has been rushed to hospital after being trapped in a machine at a busy train station.

The 52-year-old man was seriously injured while working on the tracks at Macdonaldtown Railway Station in Eveleigh , an inner southern suburb of Sydney, while at work about 1.30pm on Saturday.

He was freed by officers from the Rescue and Bomb Disposal Unit.

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Paramedics treated him at the scene for head, back and arm injuries before taking him to Royal North Shore Hospital, where he remains in a serious but stable condition with suspected spinal fractures.

The incident is being treated as a workplace accident.

“Police have secured a scene, awaiting arrival of investigators from SafeWork NSW and Staff from Office of Transport Safety Investigation,” police said.

Investigations are underway.