Belarussian hammer thrower Ivan Tikhon and Moroccan 1,500 metres runner Amine Laalou have been suspended for doping offences by the ruling athletics body IAAF and cannot compete at the London Olympics.

“Ivan Tikhon and Amine Laalou have both been charged with anti-doping rule violations under IAAF Rules. Each athlete has been provisionally suspended by the IAAF pending the outcome of a hearing,” the IAAF said in a statement on Saturday.

Tikhon is believed to be among the athletes, who were caught using forbidden substances in retests of Olympic samples from the Athens 2004 Games.

Also on Saturday, Brazilian rower Kissya Cataldo and Colombian 400 metres runner Diego Palomeque Echevarria were suspended from the London Games after testing positive for banned substances last month.

Tikhon, who won silver eight years ago, and compatriot bronze medallist Vadim Devyatovskiy were stripped of their medals for a doping offence.

But the Court of Arbitration for Sport nullified the ruling in 2010 in connection with the analysis of the sample in the lab.

Five retests of the Athens samples are believed to have had suspicious findings and the Belarussian Olympic Committee has been quoted as saying that he has already left London.

Laalou is said to have tested positive at a meet in Monte Carlo on July 20. The news comes after compatriot Mariem Alaoui Selsouli, the 1,500m world list leader, was caught at the Paris meet using the diuretic furosemide.

The Brazilian Olympic Committee said that Cataldo had been expelled for failing a doping test carried out in her home before the Olympic testing period started on July 16.

Cataldo, who was due to compete in the C final of the women’s skulls rowing event on Saturday, in which places 13 to 18 are decided, tested positive for a banned substance, believed to be the blood booster EPO, in a test carried out on July 12.

A urine sample provided by Palomeque on July 26 tested positive for testosterone, the International Olympic Committee confirmed on Saturday.

IOC spokesman Mark Adams said Saturday that the organization has so far carried out 2,905 tests to date: 2,323 urine and 582 blood tests.

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