Two people have been injured and four people have been arrested after an incident on board a train at London Bridge Station.
A British Transport Police spokesman said: "BTP and Metropolitan Police officers attended London Bridge rail station today, Wednesday 17 March, after a report of a disturbance onboard a train at the station.
"Paramedics from the London Ambulance Service also attended and two males were taken to hospital.
"Four males have been arrested in connection with the incident so far and have been taken into custody.
"The incident was reported to police at 3.36pm.
"Officers are currently making local enquiries to establish the full circumstances surrounding the incident and investigations remain ongoing."
A trail of blood could be seen through the station; part of the lower concourse in Joiner Street was taped off to allow officers to gather evidence.
Anyone with any information about the incident should contact BTP on 0800 40 50 40 quoting incident 339 of 17/03/10.