Four teenagers have been arrested after an attack at Stratford station last night which ground the underway walkways to a standstill.

Medics from London Ambulance Service treated a man, who has now been named as John Francis Breen, for serious head injuries, before taking him to hospital where he remains in a critical condition.

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 currently remain in custody.

A spokesman from British Transport Police said: “Officers are now working to investigate the circumstances of the incident and how the man came to sustain his injuries.”

Detective Chief Inspector Dave Shipperlee, leading the investigation, is now appealing to anyone who can help trace the injured man’s next of kin.

He said: “The injured man, currently in hospital, is believed to be John Francis Breen, aged 53, from London. If you know Mr Breen we need to hear from you.

“We also want to hear from any witnesses who may have been at the station and would urge anyone who saw anything to get in touch.”

Commuters complained of overcrowding and trampling and many also accused station staff of handling the situation poorly.

Zue Photography @Zuephotography took to Twitter to complain about the “dangerous” crowds, posting: “No staff to be seen (surprise surprise).” Mediamom @dekemi83 questioned: “How safe are we really when people can get stabbed at an underground station. #Stratfordstation is in absolute chaos right now. Avoid!”

Peggy Loo @peggyloo tweeted: “Complete chaos at Stratford station, people getting trampled. @TfL please control the crowd!”

And Elizabeth Sowula @elisowula posted: “Stratford station was scary tonight – no attempts to control the flow of people going in, major crushing in walkways.”

DCI Shipperlee said: “During the initial stages of the investigation it was necessary to cordon off parts of Stratford station.

“As a result we are aware there were a significant number of people who were unable to access certain sections of the station and we worked closely with the train operating companies to return the area to normal operations as soon as was possible.”

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 is asked to urgently contact BTP on 0800 40 50 40 or text 61016 quoting reference 412 of 28/10/15