A woman was left trapped on a train after its engine decoupled leaving her stranded.
Grace's has "distressing" experience happened over weekend when she couldn't escape the train carriage.
She was travelling to Cardiff to visit family on a GWR train service and became stranded when the engine split at Temple Meads station in Bristol.
Grace tried to attract attention by shouting and banging on the windows along with two others on board.
But by the time they were eventually freed, the train had moved on without them.
She told Somerset Live : "I was travelling on the 10.38am service from Bath to Cardiff on Saturday to see family.
"I have taken that train lots of times and there is usually an announcement when we reach Temple Meads, to tell you which coaches will be going on to Cardiff.
"However, that day, I am sure there was no announcement. I wasn't wearing earphones or anything, because I get sort of paranoid about the announcements, so I didn't just miss it.
"I was sitting at the very front of the train, near the engine, and there was a middle-aged couple in front of me.
"When we got to Temple Meads, I could see people queuing to get on and people getting off."
After a long wait, Grace started wondering why the train had not left yet. She got up to look around the coach and realised that she, and the couple, were the only people left.
"One of them went down the coach and they said that two coaches had been left behind and there was nobody on board, no drivers or staff.
"We knocked on the door to the engine, but the driver was definitely gone and no one could hear us.
"We tried to open the doors, but they won't open when the train is off.
"I thought about pulling the alarm, but there was nobody left to hear us, so I didn’t."
They then tried banging on the windows of the coach and shouting.
She explained that they could see some Great Western Rail (GWR) workers standing on the platform, but that they were completely oblivious to the trapped group.
"It was quite upsetting and distressing. We carried on hammering on the window and eventually, a passerby spotted us and told the rail staff
"When one of the workers let us off all he said was that the coaches had been checked - but they hadn’t because why wouldn’t he have seen us?
"I have taken the train to Cardiff before and normally we hear an overhead announcement and I am sure that no one did a walk-through to check the coaches were empty," Grace said.
She added that she had purchased a restricted ticket which only allowed her to travel on that particular train. When she was finally freed, she went to the ticket office to ask what she should do.
"The lady there was horrified to hear what had happened to me and she wrote a note on my ticket, signed with her employee number, to allow me to get on the next train and to make sure they let me out of the station at Cardiff.
"However, by the time I eventually arrived, the family commitment I had been going for was over. The ticket lady told me to message GWR Help on Twitter, but so far I have not had a response."
A GWR spokesman said: "These trains often detach at Bristol Temple Meads and split into two: an announcement is/should be made on board advising people of this and which part of the train they need to be in for the onward journey to Cardiff.
"Depending on the train type, usually speaking, the train will decouple and then the doors will be released allowing people to get off (and board), or the doors will be released allowing people to alight; then the train will decouple, and the corresponding portions checked.
"A member of staff was providing assistance to a customer in a wheelchair in the rear set.
"Once the wheelchair from the rear set had been dealt the staff member moved to the front set and helped the lady off the train.
"Apparently, she was extremely kind and understanding about the slight delay."