Six world-class Russian race-walkers including a reigning European champion have been suspended after failing doping tests a year before the Olympics.
Track and field's world governing body the IAAF says the six all tested positive during out-of-competition testing in June in the Russian city of Saransk, home to a training facility with links to more than a dozen previous doping cases.
Among those suspended is Elmira Alembekova, who won European gold last year, and Mikhail Ryzhov, winner of the silver medal in the 50-kilometer race at the 2013 world championships.
In July, Russia withdrew its entire walk team from the world championships the following month, saying it suspected possible doping, but did not reveal that the six athletes had already tested positive.