LAUSANNE, Switzerland (AFP) – Five canoeists including a gold medallist and a five-time world champion became the latest Russian competitors to be banned from next month’s Rio Olympics after an explosive report revealed state-run doping across Russian sport.

Their exclusion takes the number of Russians banned from taking part in Rio to 18 since Sunday, when the International Olympic Committee controversially opted not to ban all Russian competitors, instead leaving it up to each sport to decide what to do.

The International Olympic Committee (IOC) faced tough criticism from top anti-doping leaders over the decision, including accusations that it had failed to show leadership in the battle for drug-free sport.

IOC president Thomas Bach insisted the unprecedented eligibility criteria put in place for Russians had teeth, with the country’s athletes having to clear “the highest hurdles” before going to the Games, which start in just 10 days.

International Canoe Federation (ICF) secretary general Simon Toulson issued a strong rebuke to suspected dopers.

“If you step out of line you won’t make the start line,” he said in a statement.

“The International Canoe Federation has taken swift action to remove five Russian canoe sprint athletes from the Rio Olympic Games following the release of additional information naming those implicated by the McLaren report,” the ICF said.

The report by Canadian law professor Richard McLaren for the World Anti-Doping Agency (WADA) detailed an elaborate doping system in Russia directed by the sports ministry that affected more than 30 sports.

Twenty-five canoe sprint athletes were named in the damning report issued last week.

The ICF said the banned five were being hit with “an immediate suspension pending further investigation making the offending athletes ineligible to compete at the Rio 2016 Olympic Games”.

The five were named as Elena Aniushina, Natalia Podolskaya, Alexander Dyachenko, Andrey Kraitor and Alexey Korovashkov.

Korovashkov, a five-time world champion, won a bronze medal in London four years ago and Dyachenko won gold in a doubles kayak sprint.

The Olympics begin on August 5, giving sports federations precious little time to deal with Russian competitors, some of whom are already in Brazil.

In addition to the ban on Russia’s entire track and field team over doping, seven swimmers, two weightlifters, a wrestler and three rowers have all also been barred.

Four-time world breaststroke champion Yulia Efimova announced plans on Monday to appeal her ban at the Court of Arbitration for Sport.

The Lausanne, Switzerland based CAS was not immediately available to comment on when an appeal would be heard, but the court and federations appear likely face a race against the clock to manage a flurry of Russia doping cases before the opening ceremony.

Russian sports minister Vitaly Mutko — a key figure in the McLaren report who has been banned from Rio — has voiced confidence that the “majority” of the country’s 387-member team would be declared eligible for Rio.