A boy of five was stranded in the dark at a station after the train doors suddenly closed on his parents after he had got off.

Samuel Lander's family were just about to follow him onto the platform at Polegate station when their train unexpectedly moved away.

Kelvin and Sarah Lander watched in horror as their train slowly gathered pace while Samuel stood alone on the platform shouting: "Mummy, Daddy".

As panic set in, Mr Lander frantically pressed the button to open the doors but without success and they could not find an emergency cord.

Mr Lander, 45, immediately dashed up the train to tell the conductor his son was left behind on the platform.

The conductor tried to call Polegate station - but found it was unmanned.

Print consultant Mr Lander then dialled 999 on his mobile phone and the police managed to locate Samuel on the platform using CCTV cameras.

Two women who saw Samuel alone stayed with him until police arrived. In the meantime, the train continued on to Eastbourne.

It was there that Mr and Mrs Lander, of Lundy Walk, Hailsham, caught the next train back to Polegate station to be reunited with Samuel, who attends Hawkes Farm Primary School in Hailsham.

The experience has left the family wary of train travel.

Part-time receptionist Mrs Lander, 34, said: "My immediate reaction was one of horror. I just burst into tears as the train moved off. I was panic-stricken.

"It was dark, Samuel was alone on the platform and we were worried about what would happen to him. I was in a right state."

The family were on a day-trip to Brighton and Mr and Mrs Lander had parked at Polegate to make the rest of the journey with Samuel and his three-year-old brother Christopher by train.

Mrs Lander said: "It is a saving grace that it was Samuel who was stranded on the platform and not his younger brother Christopher.

"Samuel looks old for his age and is a sensible boy. If it had been Christopher then who knows what could have happened. When we found out Samuel was fine, it was a great big relief for us.

"We found out he was in a police car playing with the controls. I gave him a big hug when I was reunited with him and told him what a brave boy he had been."

Southern said they have sent the Landers flowers and teddy bears while an investigation is launched into the incident.

A spokesman for the rail operator said: "We will be looking into what happened and reporting back to the family accordingly.

"Regardless of the outcome of the investigation, we recognise that this was a distressing incident and will be looking into it."