A rail passenger was stabbed to death in front of his teenage son by another traveller who accused him of blocking the aisle, a court has heard.

Lee Pomeroy, 51, was knifed 18 times after getting into a row with 36-year-old Darren Pencille on board the Guildford to London train on January 4, the Old Bailey was told.

After attacking the father of one, Mr Pencille, allegedly fled at the next station and was picked up by his girlfriend Chelsea Mitchell, 27, who is accused of buying hair clippers and razors in order to help him change his appearance.

Opening the case against him, prosecution barrister, Jake Hallam QC, described how the initial exchange between the Mr Pomeroy and his alleged attacker had been "fast moving, unexpected and tragic".