A man has been arrested on suspicion of murder after a train passenger died on a platform following an altercation in a carriage on Saturday night.
British Transport Police (BTP) officers were called to Platform 8 of Reading station in Berkshire at 11.43pm, where they found the injured man, aged 24, who was later pronounced dead.
His family have been informed and they are being supported by specially trained officers.
A 42-year-old man arrested at the scene on suspicion of murder remains in police custody.
Detective Chief Inspector Paul Langley appealed for witnesses to help officers understand what happened.
He said: "This is a needless act of violence which has resulted in the tragic loss of a man's life.
"Officers were quickly able to make an arrest at the scene and a man remains in custody this morning.
"While we are still in the very early stages of our investigation, we believe the men had an altercation on board a train before the victim was assaulted on Platform 8
"Witnesses will be crucial in helping us piece together exact what happened last night, and I would urge anyone who may have witnessed the incident or the moments before it to contact us as soon as possible."
Anyone with information should contact British Transport Police by texting 61016 or calling 0800 4050 40 quoting reference 665 of 30/07/22.