The International Association of Athletics Federations (IAAF) has initiated disciplinary action against 28 athletes after they retested samples from the 2005 and 2007 world championships with new technology that can uncover previously undetectable substances and found 32 adverse doping cases, Reuters reports.
Eastern Europeans, including Russians, make up a large number of the 28, sources familiar with the testing told.
They were not aware of any Americans on the list and the BBC reported there were no British athletes.
The world athletics governing body said it could not yet name the 28 or even their nationalities, “due to the legal process”.
“A large majority of the 28 are retired, some are athletes who have already been sanctioned, and only very few remain active in sport,” the International Association of Athletics Federations said.
“The IAAF is provisionally suspending them and can confirm that none of the athletes concerned will be competing (at the world championships) in Beijing.”
The 2015 world championships start in the Chinese capital on Aug. 22. The tests were the second for samples from the 2005 world championships in Helsinki.
The first, in 2012, revealed six adverse findings. Five of the six were medal winners, all representing either Belarus or Russia.