Maria Komissarova undergoes six hours of surgery after breaking back in practice

Russian freestyle skier Maria Komissarova has undergone more than six hours of surgery after she broke her back during a practice run at the Winter Games in Sochi.

Komissarova crashed at the PSX Olympic skicross venue at Rosa Kuhtor, fracturing a vertebra and dislocating her spine in the process.

Mikhail Vezhba told the RIA Novosti news agency: "The operation lasted six-and-a-half hours, and it was successful. We'll know more about the details later."

According to the news agency, the skier was left in "unbearable" pain following the crash.

Komissarova had injured her leg last year, which kept her out of action for almost six months.