The Russian Anti-Doping Agency says it has begun an investigation into the country's dominant race-walking team after several athletes were banned.
RUSADA says on Friday it opened "a preliminary investigation into possible breaches of anti-doping rules in relation to athletes' staff" because of "multiple disqualifications of athletes."
RUSADA has requested biological passport data on athletes from the IAAF.
The move follows an online campaign led by Australian Olympic walking medalist Jared Tallent against Russia coach Viktor Chegin, who Tallent says has overseen 17 of his athletes banned for doping.
The latest was reigning Olympic 20-kilometer champion Elena Lashmanova, who was suspended for two years last month after testing positive for banned substance GW1516.