Discus medallist fails drug test

Darya Pishchalnikova failed a drugs test ahead of this summer's Olympic Games, it has been revealed.

It has been confirmed that the Russian athlete tested positive for an anabolic steroid from a sample taken in May this year.

The 27-year-old won the silver medal in London, and is the reigning world discus champion.

The governing body of world athletics, the IAAF, has opened an investigation.

Pishchalnikova faces a life ban if found guilty, having already served a ban for doping ahead of the 2008 Olympics in Beijing.

She denies any wrongdoing.