COPS are baffled as to why this teenager met a horrific end on a railway track late at night.

Kofi Ofori-Attah, 18 - a student from Waterloo - was found dead 50yds outside Balham station by workmen last week.

Post-mortem tests showed the young man had been run over by a train - yet no driver has reported hitting anyone. His family paid tribute to a bright and popular sports fan who was looking forward to a career in business.

Police admit the circumstances surrounding the tragedy are a mystery.

Kofi's grieving step-father, Kwasi Ansah, said: "He was an outgoing person.

"He was very bright and well-liked by his peers - a young man who would always help people.

"None of us can believe he is gone. We love him so much and will dearly miss him."

Kofi lived with mum, Diana, step-dad Kwasi, and his three sisters and brother in Upper Ground, off Blackfriars Road.

Mr Ansah says he was a keen Manchester United fan, and was studying tourism and leisure at John Ruskin College, Croydon.

Last Tuesday evening he went out with pals, but was found dead at 1am the following morning.

Detective Inspector Alan Jenkinson, investigating, said: "It's an absolute mystery.

"Here we have a young man full of life and in perfectly good health, who had everything to live for.

"Why he came to be on those tracks at that time is completely unexplained."

His team are appealing for witnesses to come forward, who may have seen Kofi at Balham overground station.

DI Jenkinson said: "We know that he had been driving around London with his friends for most of the evening.

"They had stopped in Waterloo for a Chinese meal earlier on and the victim had been dropped off at Balham station at around 10pm.

"We would like to hear from anyone who was in the vicinity and may have seen something between 10pm on Tuesday and 12.30am on the Wednesday.

"It's a busy area so someone might easily have seen something."

DI Jenkinson refused to comment on whether it was being treated as a murder investigation.

"At this stage we have to keep an open mind," he said.

An inquest was due to be formally opened yesterday and adjourned.

Information to 0800 405 040.

Balham overground station was shut until Wednesday lunchtime, causing massive delays to surrounding rail services.