A Greater Anglia passenger was fined after she stood "in the doorway" of the First Class carriage on a packed train.
The woman said she was standing there because "there was nowhere else to stand" - but Greater Anglia said first class carriages, including the vestibules and aisles, are for the use of first class ticket holders only.
In a video, the woman can be heard saying the incident was ridiculous as she hadn't even sat down on the busy train.
The commuter,thought to have been travelling home from work to Colchester, was stopped by a ticket inspector at Shenfield around 6.45pm on Wednesday.
Prasad Iyer, 25, from Chelmsford was on his way home and saw it unfold.
He told Essex Live: "It was a really crowded train and it was already full. I was standing right by the door in the last carriage and I saw the ticket inspector get on because he walked past me.
"There were lots of people standing, but the lady was in the doorway of First Class section and he made a beeline for the her.
"The first thing I heard was 'where were you standing?'
"The conversation had been going on for a bit and he said 'you don't have a First Class ticket.'
"She was trying to explain herself and he kept on asking 'where were you standing?'
"She was standing there because there was nowhere else to stand. She had moved to the left because people were trying to get on the train."
In a video filmed by Prasad, the woman can be heard saying: "I'm not saying I have a First Class ticket but there was nowhere to stand, but I stood, I did not sit.
"There was nowhere else to stand, the train was packed. This is ridiculous."
Prasad claims he then saw the inspector take the woman's ticket off of her to scan and called over a second man to give the woman the fine.
He claims he and a few other commuters then stepped in to ask the ticket inspectors how they could take her ticket off of her.
Other commuters took to Twitter after the incident to complain about what had happened.
He added: "It was ridiculous.
"The lady said that she pays around £6,000 per year to get between Stratford and Colchester and rarely ever gets a place to sit.
"As someone who gets the train to London from Chelmsford for work, I think that it's overpriced and overcrowded.
"But this scene really kind of combined everything that's terrible in one incident."
A Greater Anglia spokesperson said: “First class carriages, including the vestibules and aisles, are for the use of first class ticket holders only.
“If the customer would like to appeal the penalty fare, they can do so via IRCAS.
“Passengers must have the correct ticket for the time and class of their journey when travelling on one of our trains.
“We would encourage the woman to contact us direct if she is unhappy with how the situation was handled.”
