The ongoing Russian doping scandal _ with the country's officials, coaches and athletes accused of systemic cheating _ could take a while to clean up.
On Friday, the International Olympic Committee announced that it has opened disciplinary cases against 28 athletes whose urine samples were allegedly manipulated in a testing lab during the 2014 Winter Games in Sochi, Russia.
The cases were triggered by the most recent report from Richard McLaren, an independent investigator commissioned by the World Anti-Doping Agency.
"The IOC will go beyond the findings of the (McLaren) Report by re-analyzing all the samples of all the Russian athletes who participated in the Olympic Winter Games Sochi 2014 as well as all those who participated in the Olympic Games London 2012," IOC President Thomas Bach said.
Twenty-seven Russians already have been sanctioned following re-tests on samples from London and the 2008 Beijing Summer Games.
Russian President Vladimir Putin has repeatedly denied allegations of state-sponsored cheating and has blamed whistle-blowers for fabricating evidence.
With several of their athletes caught up in the latest investigation, Russian cross-country skiing officials have decided not to host the 2017 World Cup finals, asking that the event be moved elsewhere while they work to repair their credibility within the sport, the International Ski Federation said.
