London's Metropolitan Police have opened an investigation after British Olympic great Mo Farah made stunning revelations he was illegally trafficked into Britain as a child.

The 39-year-old Somalia-born athlete – who won double Olympic gold (5,000-meter and 10,000-meter) for his adopted country at both the 2012 and 2016 Games – revealed in a BBC documentary this week his real name is Hussein Abdi Kahin.

He said he was forced to work in domestic servitude after entering the country aged eight or nine.

"We are aware of reports in the media concerning Sir Mo Farah," said the Metropolitan Police in a statement Thursday.

"No reports have been made to the MPS (Metropolitan Police Service) at this time. Specialist officers have opened an investigation and are currently assessing the available information."

Farah was helped to obtain U.K. citizenship by his physical education teacher at school, Alan Watkinson, while still using the assumed name Mohamed Farah given to him by a woman who trafficked him to Britain.

On Wednesday, Farah was assured by the British Government he would not be stripped of his citizenship with a spokesman for Prime Minister Boris Johnson describing him as "a sporting hero."

Rather than moving to the U.K. as a refugee from Somalia with his mother and two of his brothers to join his IT consultant father as previously claimed, Farah said he came from Djibouti with the woman he had never met, and then made to look after another family's children.

In fact, he said, his father was killed in civil unrest in Somalia when Farah was aged four and his mother, Aisha, and two brothers live in the breakaway state of Somaliland.

His cousin Harun Aden – who also lives in Somaliland – told The Times that Farah's father Abdi, a farmer, had been killed by shrapnel from a bazooka and the youngster had been sent to live with an uncle in Djibouti.

"Mo was very young and could not work and it was a time of poverty and war," said Aden.

"He was sent to Djibouti to save his life and help his family because they could not care for him."

Aden says he calls Farah by his birth name Hussein: "Mo is like his nickname to us."

Aden – a father of nine who was left disabled after being shot – says Farah has looked after his closest family, paying for their houses with the money he has made during his stellar career.

"He supports his mother and siblings," said Aden.

"I haven't had any money from him but I am not upset about that. He has worked very hard for what he has and it is enough for me that he helps others who need it more."

Farah said he was proud to have represented Britain as an athlete but that his "proudest achievement will always be being a husband and father to my amazing family.″

"I did this documentary for them, so they could understand more about the experiences that led us to becoming the family we are today,″ he said in a social media post.

"Not every child will have the easiest start in life, but that doesn’t mean they can’t go on to achieve their dreams,″ he added.