A 27-year-old woman has also been arrested
Police have arrested a man following the
fatal stabbing of a passenger on a train to London Waterloo.
A 51-year-old man was stabbed to death in front of his teenage son while travelling on a Friday afternoon train service.
Police and ambulance services were called to Horsley station, Surrey, after reports a man had been stabbed on board the 12.58pm South Western train service travelling between Guildford and London Waterloo.
He received medical attention but, despite the efforts of police officers and paramedics, died at the scene.
A suspect was arrested at an address in Farnham. A 27-year-old woman was also detained on suspicion of assisting an offender.
British Transport Police's DCI Sam Blackburn said: "This is a fast moving investigation and I am pleased that overnight we were able to arrest a man following a huge amount of police enquiries.
"The investigation is moving with good progress and we are now confident to say that this is not believed to be a random assault.
"In the moments leading to the violent killing, both men appeared to be involved in an altercation lasting three minutes.
"Nothing justified the extraordinary violence that followed, and we are concentrating our efforts on the on-going investigation."
British Transport Police is still appealing for information regarding the event.
Assistant Chief Constable Sean O'Callaghan told BBC Breakfast: "We now know from enquiries we've been doing overnight and from witnesses that the two men were involved in a verbal discussion, that discussion lasted three to four minutes, it moved through one carriage from where they first boarded into another carriage, and that argument escalated to the unprovoked violent attack that sadly resulted in the death.
"This is, as far as we can see at this moment in time, an incident that has occurred when two men have been talking to one another, opposed to a random attack on a train.
"Travelling on the train is still an extremely safe thing to do. Very few crimes actually occur on the train itself.
"In terms of violent offences, it's one violent offence for approximately one million passenger journeys, so the chances of being a victim of violence on a train in England, Scotland and Wales is still extremely low."
Anyone with information should contact BTP by sending a text to 61016 or by calling 0800 40 50 40 – quoting reference 210 of 04/01/19.
Alternatively they can ring Crimestoppers anonymously on 0800 555 111.
