The whistleblower at the centre of doping allegations against a London-based doctor has accused UK Anti-Doping (UKAD) of a "catastrophic failure".
A report in The Sunday Times last weekend alleged that Dr Mark Bonar prescribed performance-enhancing drugs to 150 athletes - including Premier League footballers, British Tour de France cyclists, tennis players and a British boxer - a claim he denies.
Allegations made two years ago
The newspaper claimed UKAD was given information about the doctor's alleged doping activities two years ago but failed to take action, and an independent inquiry is to be held to look into the matter.
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And in an interview with BBC Sport, former amateur cyclist and drugs cheat Dan Stevens has come forward as the whistleblower.
Forty-year-old Stevens was banned for two years when he refused to give an out-of-competition sample, a suspension which was reduced by three months.
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Stevens said he found Bonar online after being diagnosed with low testosterone levels and initially found him to be a "sensible, good doctor".
But Stevens also claimed that Bonar would later talk to him about other drugs, such as human growth hormone and EPO.
He said: "I think it was quite revolutionary to meet with a British doctor in a private clinic who was telling me that a number of high-profile British athletes, cyclists, runners, boxers, cricketers and footballers were using these substances to improve their performance. His words were that this is what is needed to be done to move up a level."
"False and very misleading"
Last weekend, a Twitter account purporting to belong to Bonar on Sunday night, although not verified, described the allegations as ''false and very misleading''.
In response to Stevens, Bonar told the BBC: "Dan Stevens presented with some personal medical issues. I treated symptoms appropriately and I did not prescribe for the purposes of performance enhancement."
Press Association Sport understands that, although UKAD was made aware of general allegations against Bonar by an unnamed sportsman in April and May of 2014, the information was vague and not at the level of detail reportedly uncovered by The Sunday Times.
"I would describe it as a catastrophic failure," said Stevens.
"UKAD had absolutely no reason to not investigate Dr Bonar. They had every reason to investigate the doctor, they were given prescriptions that the doctor had produced - those prescriptions included the doctor's GMC registration number.
"They were prescribed via British chemists. UKAD have got absolutely no excuse for not investigating this, and that is a massive concern.
"It's horrendous. It's diabolical. And I don't think it's by accident either.
UKAD - who Press Association Sport contacted for a response - said in a statement to BBC Sport: "In addition to UKAD's previous statement, it is important to highlight that UKAD is investigating the claims made by the Sunday Times.
UKAD under pressure
"We must also clarify that UKAD does not have the names of any sportspeople who may have been treated by Dr Bonar other than the sportsperson concerned.
"The UKAD board has appointed [former assistant chief constable] Andy Ward to lead an independent review into UKAD's handling of intelligence in 2014 in relation to Dr Bonar and the wider investigation which took place following the sportsperson's interviews.
"UKAD will fully co-operate with the independent review."
In a statement sent to Press Association Sport, a UK Anti-Doping spokeswoman said: "In addition to UKAD's previous statement, it is important to highlight that UKAD is investigating the claims made by the Sunday Times. We must also clarify that UKAD does not have the names of any sportspeople who may have been treated by Dr Bonar other than the sportsperson concerned.
UKAD set for independent review
"UKAD encourages anyone who wishes to report wrongdoing to contact us. Intelligence, and those who provide information, are vital to our work in protecting clean sport and clean athletes. We welcome anyone who wishes to provide us with information and they will be treated in the strictest confidence. Sources of intelligence and the names of those who provide us with information are never disclosed by UKAD.
"UKAD would encourage anyone with information on doping, no matter how big or small, to contact us via reportdoping.com.
"The UKAD Board has appointed Andy Ward to lead an independent review into UKAD's handling of intelligence in 2014 in relation to Dr Bonar and the wider investigation which took place following the sportspersons interviews.
"UKAD will fully cooperate with the independent review and we will not comment further on this particular case until that review has been concluded."
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