PARIS - Jemima Sumgong, the first female Kenyan to win Olympic marathon gold when she triumphed at Rio last August, has failed an out-of-competition dope test, the BBC reported on Friday.

The 32-year-old, who is also the reigning London Marathon champion, tested positive for the banned blood booster EPO in a test by the International Association of Athletics Federations (IAAF) in Kenya, the BBC reported.

"We can confirm that an anti-doping rule violation case concerning Jemima Sumgong has commenced this week," www.bbc.com quoted the IAAF as saying in a statement.

"The athlete tested positive for EPO following a no-notice test in Kenya."

The IAAF did not respond to an AFP request for confirmation of the report on Friday.

Sumgong starred at the London Marathon last year, defying the odds to win after taking a bruising tumble.

Steeled by her success in London, she then became the first Kenyan woman to win Olympic marathon gold in Rio.

Sumgong defeated Ethiopia's world champion Mare Dibaba to confirm her status as the world's top marathon runner of the year.

Before claims of a positive drugs test emerged, Sumgong said she was anxiously looking forward to returning to London to defend her title on April 23.

"London is the marathon every runner wants to win," she said. "I can't wait to return to defend my title."

Tim Hadzima, general manager at Abbott World Marathon Majors, organizer of the world's largest marathons including London, said the organization was "distressed" by the reports, but said that "if true, they indicate we are gaining ground in our long-standing fight against doping".

At the Rio Olympics, Sumgong defied temperatures of 28 C to claim historic gold in a race that finished at the city's famed Sambodromo.

"It was very hot but everybody had to get through the heat," said Sumgong, who said that victory made up for her disappointing showing at the 2008 Beijing Olympics.

"I had to control my body and listen to it very carefully.

"I was in Beijing in 2008 but I was pretty disappointed that I wasn't able to win a medal or make it on the podium. But I was still confident that one time, one day, I'd be a champion somewhere.

"I was never worried that I'd lose in Rio. At 40km, I knew the gold was mine."

Earlier this year, Sumgong was one of a number of top Kenyan athletes who welcomed a new initiative to stop doping, which has tarnished their image, in which they agreed to be monitored by doctors appointed by the IAAF and Athletics Kenya.

Agence France-Presse