The International Association of Athletics Federations (IAAF) has re-tested the samples of athletes from the 2005 and 2007 Athletics World Championships and banned 28 competitors as a result.

However, the world athletics’ governing body refused to name the athletes “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 body said.

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“The IAAF is provisionally suspending them and can confirm that none of the athletes concerned will be competing in Beijing [at the 2015 world championships].”

The IAAF said if the violations are confirmed it would re-write the record books and re-allocate the medals from the 2005 and 2007 events as necessary.

The 2005 event was staged in Helsinki, with Japanese city Osaka playing host in 2007.

The re-testing took advantage of new testing procedures and the 10-year period now offered under IAAF rules and the World Anti-Doping Code.

“The latest scientific breakthroughs in anti-doping technology and analysis have been employed in the re-analysis of these samples to allow us to find previously undetectable substances,” Martial Saugy, director of the Swiss Laboratory for Doping Analyses in Lausanne, said in a statement.

Beginning in 2005, athletes’ samples from previous championships have been stored at the laboratory and they were used in the re-analysis.

“The findings reconfirm, yet again, the commitment of the IAAF to target and uncover all cheating in the sport, no matter how long it takes,” said the IAAF.

“The IAAF does not shy away from the fact that some athletes continue to cheat and defraud their fellow competitors.

“But we will do everything in our power, and use every tool available, to protect those clean athletes who form the large majority of our sport.”

The IAAF said the re-testing began in April, which was “well before the recent allegations” from German broadcaster ARD and The Sunday Times that were made against athletes and the body.

The 2015 World Championships start in Beijing on August 22.

None of the athletes suspended were competing at this month’s event, the IAAF said.

– with ABC