Russian doping scandal: Five walkers banned for using EPO

Mikhail Ryzhov won a silver medal in the 50km walk at the 2013 World Championships in Moscow

Five Russian race walkers have been banned for four years by the Court of Arbitration for Sport (CAS) after testing positive for banned substance EPO in June 2015.

Elmira Alembekova, Ivan Noskov, Mikhail Ryzhov, Vera Sokolova and Denis Strelkov's results from June 2, 2015 to July 15, 2015 have been annulled.

Alembekova won 20km European gold in 2014, while Ryzhov claimed 50km silver at the 2013 World Championships.

Noskov won 2014 European 50km bronze.

Strelkov was a bronze medallist in the 20km walk at the European Championships two years ago, while Sokolova - the 2003 World Youth Champion - won the European Cup in May last year.

Erythropoietin, or EPO, is a hormone which can increase endurance and, in athletics, is used mainly by long distance-runners.

It is injected under the skin and stimulates red blood cell production.

Russian athletes have been caught up in a doping scandal which resulted in the ban of 108 Russians from the 2016 Rio Olympics and a complete exclusion of the country's 267 competitors from the Paralympics.

On Wednesday, Alexander Zhukov, who headed Russia's Olympic Committee throughout the country's state-sponsored doping scandal, announced the was stepping down.