Russian doping whistle-blower Vitaly Stepanov charges in an upcoming interview with CBS television's "60 Minutes" that four of the country's gold medalists at the 2014 Sochi Winter Olympics took steroids.
Russia won 13 gold medals at the Sochi Olympics.
A brief preview of the CBS program due to air on May 8 did not reveal the names of the suspected dope cheats. But Stepanov charges that the former head of Russia's drug-testing lab told him he had a "Sochi List" of Russians who competed on performance-enhancing drugs, and four athletes on that list won gold medals.
The story could signal a widening of the doping scandal that has engulfed Russian athletics.
Stepanov appeared in a German television documentary claiming systematic doping in Russian athletics in 2014.
His allegations later were supported by an investigation by a World Anti-Doping Agency commission, whose finding of state-sponsored, widespread doping led to a ban on Russian track and field's participation in international competitions, including possibly the Rio Olympics in August.
Russian Sports Minister Vitaly Mutko told TASS on May 7 that Stepanov's accusations of doping use by Russian medalists in the Sochi Olympics are based on speculation.