Eight Russian athletes tested positive in restests of doping samples from the 2012 Olympics, according to the Associated Press.
The Russian Olympic Committee did not announced the names of the athletes or their specific disciplines, but did say that they come from three different sports.
Further information about the tests will be released after they can be confirmed or contradicted.
The positive results come from retests that the IOC does using newer testing methods on samples that have been stored for future analysis.
Russia has already been banned from competing in track and field, including at the Rio Olympics, by the international track and field federation.
The IOC said Friday that 23 athletes from five sports and six countries tested positive in retests of 265 samples from 2012.