A man was seriously injured at Whitton station when he was "hit by a train" after slipping on to the tracks on Saturday night.
London Ambulance Service (LAS) treated the man at 9.19pm, believed to be in his 20s, for head injuries before he was taken to St Mary's Hospital, London, as a priority.
Witnesses have described seeing the man fall on to the tracks before being "hit by a train".
An LAS spokesman said it sent a single responder, a car, a duty officer and an advanced paramedic to attend the scene.
The incident caused delays and alterations to trains running through Whitton.
South West Trains tweeted: "Delays and alterations to London bound trains travelling through #Whitton and Twickenham due to emergency services dealing with an incident."
Did you see what happened? Call the news desk on 0208 722 6330 or email tom.ambrose@london.newsquest.co.uk
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