Terrified commuters were caught up in a “dangerous” rush-hour crush at one of London’s busiest stations after a man was brutally attacked by a gang.

Scenes of chaos hit Stratford station as staff struggled to marshal panicking crowds blocked from reaching overground platforms as they poured off the Jubilee line.

Witnesses said a child was “trampled” amid the jostling and confusion yesterday evening, with another passenger branding the situation “ridiculously chaotic”.

Problems began after 5pm when a man was attacked and collapsed unconscious with serious head injuries in the western underground walkway that links the overground rail platforms to the Westfield shopping centre and Jubilee line.

Transport for London today defended its decision not to close the station, saying staff believed that it was better to keep trains running to help disperse the crowds.

But witness Nick Paget, 28, a parliamentary researcher for Labour MP Gloria De Piero, told the Standard: “No one was in control. It was an accident waiting to happen. It was only luck that it didn’t. Everyone streamed off the Tube lines but they couldn’t get anywhere.”

"It was really unsafe for everyone in the station." Peggy Loo

Peggy Loo, 33, an accountant from Stratford, said: “Nobody seemed to be trying to control the situation or realised how overcrowded it was. The attendants looked completely overwhelmed and it was really unsafe for everyone in the station.”

Peter Coleman, 64, a poppy seller on the platform, said: “It was mayhem. They shut the tunnel off, then people were trying to get over to the other side where the other tunnel to the platforms are. There were thousands of people.”

Jesus Manso Arcas, 32, a food importer who lives in Stratford, said: “We all started to fear for our safety and that people were going to get hurt, because people started pushing each other and if it had gone on much longer I think there could have been casualties. It was mayhem. They should have a better system for dealing with these things.”

Melissa Simpson, 25, a journalist, said: “It was horrible. I get claustrophobic and it was jammed with people. They should have just evacuated the station.”

Miles Tudor said: “I travel through Stratford daily and fear a serious incident is looming involving the crowded platforms. Last night there should have been a full halt on the trains and Tubes arriving, it felt quite out of control.”

Witnesses told the Standard that the injured man, named today by police as John Francis Breen, a 53-year-old Londoner, suffered a “brutal beating” on the London Overground platforms 1 and 2 and may have suffered further injuries falling down the stairs to the walkway before suffering a cardiac arrest.

The assailants are believed to have fled to the Jubilee line.

Prafal Thakrar, 51, who works in Expresso Coffee, said: “It was a gang of four people who attacked the person.

“It started in the West tunnel at platforms 1 and 2 and the [assailants] then legged it onto platform 13.

“Everyone started dialling 999 and they had to stop the train and they closed the platform so they couldn’t run off.”

Police closed the walkway to allow paramedics and a doctor from London’s Air Ambulance to give emergency treatment, while detectives sealed off the scene of the assault to begin an investigation.

Mr Breen was today in a “critical but stable” condition in hospital. Two 14-year-old boys, a 15-year-old boy and a 16-year-old boy were arrested on suspicion of grievous bodily harm and are in custody.

Detective Chief Inspector Dave Shipperlee, of British Transport Police, said: “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.”

He added: “During the initial stages of the investigation it was necessary to cordon off parts of Stratford station. 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.”

Steve Griffiths, chief operating officer for London Underground, said: “We appreciate our customer’s 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.”

Witnesses should contact BTP on 0800 40 50 40.