In track and field, new anti-doping tests of old samples — taken from athletes at the 2005 and 2007 World Championships — have brought a flurry of suspensions. The sport's world governing body says it's punishing 28 athletes over the findings. It did not release any of their names or nationalities.

The International Association of Athletics Federations is calling the suspensions its "latest success," but the organization also says "a large majority" of the 28 athletes have already retired and that others have already faced sanctions.

None of the suspended athletes were scheduled to compete in this year's World Championships in Beijing, the IAAF says.

The samples from the earlier championships held in Helsinki and Osaka had been stored under a revised anti-doping policy that provides for retesting when technology has caught up with substances that athletes use to cheat. The current statute of limitations on doping is 10 years, according to the World Anti-Doping Code.

"In our 10-year partnership with the IAAF, we have been using every scientific advance and legal opportunity at our disposal to catch the cheats," says the head of the Swiss Laboratory for Doping Analyses, Martial Saugy.

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