A murder inquiry has been launched following an attack at Stratford station last night, which ground the underway walkways to a standstill.

John Francis Breen, 53, had been treated for serious head injuries, but died this afternoon as a result of the assault.

British Transport Police said they were called at 5.18pm to reports of an unconscious man with injuries at the station.

Two 14-year-old boys, a 15-year-old boy and a 16-year-old boy have all been arrested on suspicion of grievous bodily harm and remain in custody.

Detective Chief Inspector Dave Shipperlee, of the British Transport Police, said: “We continue to investigate the circumstances of the incident and are still in the process of interviewing the four teenagers arrested last night.

“Our sympathies go out to Mr Breen’s family and I would like reiterate our appeal for witnesses to help us piece together exactly what happened.

“We have already heard from several people who were at the station, and I would like to thank those who have come forward.

“I am certain there will be more people who can not only help us with our investigation, but can also provide information that will assist Mr Breen’s family in understanding how he sustained such traumatic injuries.”

The London Ambulance Service were called at 5.12pm to reports of an assault.

A spokeswoman said: “We sent a number of resources to the scene including a single responder in a car, an ambulance crew and the medical team from London’s Air Ambulance in a car to the scene.

“We treated one patient, a man, who was in cardiac arrest. He was taken to hospital as a priority.”

Steve Griffiths, chief operating officer for London Underground, said: “We appreciate our customers’ patience during the police incident at Stratford yesterday evening.

“Our station staff worked hard to keep the station open in order to allow people to leave the area.

“We monitor such incidents carefully and our priority always remains the safety of our customers.”

Anyone with information should contact police on 0800 40 50 40 or call Crimestoppers, anonymously on 0800 555 111, quoting incident 412 of 28/10/15.