A boy and his friend were left stranded in Bexhill by 'intimidating' train staff, an angry mother claims.
Susan Piper, of Norman Road, St Leonards, said her 12-year-old son Tyler and Jamie Ashcroft, also 12, were slapped with a fine after accidentally boarding the wrong train.
She said: "My son and his friend caught a train from St Leonards Warrior S
quare, intending to get off at West St Leonards to see a friend.
"They bought a ticket from the ticket machine on the platform which cost them 75p each.
"Seeing a train coming, they boarded it thinking it was the correct one. They were unable to ask for assistance as there were no staff available."
Tyler and Jamie realised they were on the wrong service when a ticket inspector checked their tickets.
Mrs Piper said: "This was their first time travelling on a train without an adult and was an experience they were looking forward to.
"They became frightened and scared and got off at the next station, which was Bexhill.
"There were three inspectors checking tickets at the exit and asked my son and his friend for theirs."
She said the two boys were told their tickets were not valid as they had got off at Bexhill instead of West St Leonards.
The pair had to pay £1 each to upgrade their tickets before inspectors took down their details and issued them with a £20 penalty fare notice with £1 deducted.
Mrs Piper said: "Both boys felt very intimidated by the ticket inspectors' height and stature and were unable to explain the situation due to anxiety.
"They felt stranded and were not offered directions.
"The inspectors should have showed them how to get the right train to where they wanted to go but instead told them it was a one-and-a-half hour walk back to St Leonards."
Tyler and his friend asked a passer-by outside Bexhill station how to get back home and got as far as Glyne Gap before contacting his mum.
Mrs Piper said: "The boys were treated unjustly. They made a genuine mistake and were afraid for their safety."
She tried to appeal against the fines unsuccessfully and had to pay £59, following the incident which happened on September 3.
Last month her 12-year-old son was even threatened with a £1,000 fine and/or three months imprisonment by debt collectors unless the penalty fare was paid off.
A spokesman for Southern said: "This case has been through due process, ending with a ruling by the Independent Penalty Fare Appeal Service (IPFAS). Now that this has run its course and the service has given its decision, we are unable to enter into any further dialogue on the matter of the penalty fare itself.
"However, there is now a question over how the young man was treated by Southern Revenue Protection staff on arrival at Bexhill station. Now that we have this information, we will conduct an investigation into the matter."