Commuters were left stranded for more than three hours on a broken down train - even though it was only 50 yards from a station.
They were ordered to stay on board by a guard despite being so close to the platform at Shenfield, Essex.
About 400 commuters were finally put on another service almost four hours after the London to Norwich train came to a halt on Thursday evening.
A spokesman for One Anglia trains said they would be looking into the case.
One traveller said the conductor threatened passengers with arrest if they fled the train.
Christopher Smith, 34, said: "We were treated abysmally and I will be writing to complain.
"We were on the train waiting for hours and it was very frustrating because you could see the station was only about 50 yards away.
"But the guard told us to stay where we were and said anyone getting off the train would be arrested.
"I saw about 20 or 30 people running across the tracks."
Mr Smith, an IT training manager who works in London and lives in Chelmsford, said his routine 29-minute journey ended up taking more than three hours.
He said: "People on our train were quite laid back - but in other places they would have been breaking down the doors."
However, a spokesman for British Transport Police confirmed that doors had been forced on the train.
He said: "Leaving the train is an extremely dangerous thing to do."
The train was eventually towed into Shenfield station - about 20 miles from London - where commuters were shepherded on to another service.
The One Anglia spokesman added: "The problem is that station is very busy with trains going into and out of Liverpool Street.
"We have to keep the railway running while trying to recover the train.
"There were 300-plus passengers on the train and to supervise an evacuation is difficult unless you close down the railway.
"The train is also fairly high up and getting people off would have been difficult."