Nine athletes were suspended yesterday for doping offences, just 48 hours before the launch of the London 2012 Olympic Games.
The suspensions mark an aggressive crackdown on drugs cheats by the International Association of Athletics Federations (IAAF).
Six of the competitors suspended were caught in "biological passport" tests, which measure changes in an athlete's blood profile, the IAAF confirmed. Another three were apprehended in re-tests of samples from last year's world championships.
The nine drugs cheats – all track-and-field athletes – included three Russians, two Ukrainians, one Bulgarian, one Greek and one Turkish national.
Inna Eftimova of Bulgaria tested positive for synthetic growth hormone, while the samples of Ukrainians Nataliya Tobias, pictured, and Antonina Yefremova both contained traces of synthetic testosterone. All three have been banned for two years.
The Moroccan runner Abderrahim Goumri was among six athletes who were monitored after irregularities showed up in their "biological passports".
The others were Russians Svetlana Klyuka, who finished fourth in the 800m at the Beijing Olympics; the 2011 European indoor 800m champion, Yevgeniya Zinurova; and Nailiya Yulamanova; along with long-distance runners Eirini Kokkinariou of Greece and Turkey's Meryem Erdogan.
The three Russians and Erdogan admitted their guilt and were given two-year bans. Goumri was handed a four-year ban by the Moroccan athletics federation, while the IAAF is looking to enforce a ban of four years on Kokkinariou.
The nine suspensions came after it was revealed that the Moroccan 1,500m runner Mariem Alaoui Selsouli had also tested positive for a banned diuretic.
In a separate, unprecedented development, the Greek triple jumper Paraskevi Papahristou also found herself expelled from the Games yesterday: her crime was posting Twitter remarks deemed to be racist.
Papahristou, 23, posted a tweet saying: "With so many Africans in Greece… At least the West Nile mosquitoes will eat home made food!!!"
This was a reference to an outbreak of the West Nile virus, a potentially fatal disease transmitted by mosquitoes of African origin, in Athens this summer.
She also re-tweeted a comment from Ilias Kasidiaris, a politician with the far-right Golden Dawn party, criticising Prime Minister Antonis Samaras's stance on immigration.
The IAAF said it now plans to conduct 200 more athlete biological passport tests at the Olympic Village.
An unprecedented 6,250 athletes competing in this year's Games will be tested for 240 banned substances in what has been billed as the most hardline anti-doping campaign in Olympic history.