Trains through Wimbledon are being delayed by up to an hour after a man was fatally struck.
The incident, reported at 1.30pm, means that South West Trains services are being held up after emergency services took control of two of the lines.
The disruption is affecting trains around Wimbledon, including from Surbiton and Kingston.
A British Transport Police (BTP) spokesman said: “BTP officers were called to Wimbledon rail station on Wednesday, 31 October after a report of a man being struck by a train.
“The incident was reported to BTP at 12.55pm and was also attended by Metropolitan Police.
“Medics from London Ambulance Service also attended but the man was pronounced dead at the scene.
“The incident is currently being treated as non-suspicious.
“Enquiries are ongoing to establish the identity of the man and inform his family."
The train involved was the 11.54am Basingstoke to London Waterloo service.
Kevin Whincup, who was at the station shortly after the incident, said: “I’m currently outside and there are three ambulances here and lots of BTP as well as the normal met police and obviously network rail are one site.
“I don’t know what else is going on.
“People are getting in but they have closed off platforms 5, 6, 7,and 8.
“They are working on the track at the moment.”
UPDATE: 5pm - Trains are now running as normal through Wimbledon station but with knock on delays to services.