The IAAF said test samples from the gold- and silver-medal-winning winning athletes from Russia and Belarus were reanalyzed and found to contain banned substances, The New York Times reported Friday.
The list includes shot putters Nadzeya Ostapchuk and Andrei Mikhnevich and hammer throwers Ivan Tsikhan and Vadim Devyatovskiy of Belarus, and hammer thrower Olga Kuzenkova and long jumper Tatyana Kotova of Russia.
Ostapchuk also was stripped of her gold medal from the 2012 Olympics after testing positive for an anabolic steroid, the newspaper noted.
"The IAAF's message to cheaters is increasingly clear that with constant advancements being made in doping detection, there is no place to hide," IAAF President Lamine Diack said.
The governing body did not specify which banned substances were found in the re-examination.