A passenger was punched in the face on a London to Northampton train at the weekend, British Transport Police have revealed.
Officers are appealing for information after the victim was attacked on the train in the early hours of Sunday morning.
The altercation took place on board the 12.15am Euston to Northampton service.
BTP and Metropolitan Police officers met the train at Wembley Central station and a 52-year-old man was arrested for being drunk and disorderedly.
He was later released on bail pending further enquiries.
PC Tim Tubbs, the investigating officer, said: “We are currently working to establish the full circumstances surrounding the altercation.
“As part of our enquiries, I am urging anyone who was on board the train, or who witnessed the incident, to come forward and assist officers in this investigation.”
“We will have officers at stations and on trains on Saturday night and Sunday morning speaking to members of the public, reassuring passengers and handing out witness appeal leaflets.”