Russia could face a ban from all major sports events over “discrepancies” in a lab database, the World Anti-Doping Agency has warned.
The country has been given three weeks to explain “inconsistencies” or risk being excluded from the Olympics and world championships.
Russia also faces being barred from hosting major events.
“There’s evidence this data has been deleted,” chairman of Wada’s compliance panel, Jonathan Taylor, told BBC Sport.
“We need to understand from the Russian authorities what their explanation is.”
