Olympic gold medalist Mo Farah has revealed he was trafficked to the UK as a child and forced into child labour.

The British long-distance runner and double Olympic champion is known to the sporting world as Sir Mohamed “Mo” Farah. But his real name is Hussein Abdi Kahin. He got the name under which he became world famous from human traffickers who had exploited him for years.

Farah reports in a BBC documentary that is scheduled to air on Wednesday. The athlete had previously said that he came to Great Britain with his parents as a refugee from Somalia as a child.

In fact, he was taken away from home when he was only eight or nine years old. Way from Somalia to Djibouti, from where he was taken to Great Britain by an unknown woman. She told him he was being taken to Europe to stay with relatives.

His name is Mohamed now, the woman said. And she had fake travel documents with that name and his photo and that’s how he became “Mohamed Farah”.

Sir Mo says he was around eight or nine years old when he was taken away from home to stay with his family in Djibouti. He was then flown to Britain by a woman he had never met and was not related to.

But when he arrived in London he did not see any relatives, the woman took him to an apartment in Hounslow in west London. There she took the piece of paper with the contact details of his relatives from him – and tore it up in front of his eyes. “Right in front of me she tore it up and threw it in the bin. In that moment, I knew I was in trouble,” Farah says in the documentary.

The woman said to him: “If you ever want to see your family again, don’t say anything.” From then on he had to take care of the children of another family and do housework “if I wanted to have food in my mouth”.

“A lot of times I’d just lock myself in the bathroom and cry,” he says. “For years I just blocked it out,” says Fahrah. “But you can’t hide it forever.”

Farah’s family didn’t allow him to go to school for the first few years, and it wasn’t until he was twelve that he entered seventh grade – although he could hardly speak English. The people posing as his parents never attended parents’ evenings.

It was Farah’s physical education teacher who made an observation that would change his life forever: “The only language he seemed to understand was the language of sport and sports,” he says. It became Farah’s lifeline. “The only thing I could do to get out of this [living situation] was to go out and run,” said the exceptional athlete. Finally, he even confided in his physical education teacher, revealed his true identity and origins – and that he had had to do child labor for years. The teacher alerted social services.

“I still missed my real family, but things got better from that moment,” says Farah. His real parents have never been to the UK – his mother and two brothers live on their family farm in Somalia. His father was killed in civil unrest when Farah was little.

A few years later, Farah gained notoriety as an athlete. At the age of 14 he was invited to compete for English schools in a race in Latvia – but he had no travel documents. His PE teacher helped him apply for British citizenship. It is considered unlikely that this will now be withdrawn from him again because it came about through fraud.

With his story he wants to draw attention to the fact that many people feel the same way. He says, “What really saved me, what made me different, was that I could run.”