British sprinter Nigel Levine, a double European gold medallist and three-time world medallist, is alleged to have failed a drugs test.
According to The Daily Mail, it is claimed that a wide number of sources from inside athletics are aware that the 28-year-old has tested positive for the banned substance clenbuterol.
Levine is reportedly awaiting the result of his B sample.
Clenbuterol is an asthma drug but has a history of abuse in sport because of its performance enhancing qualities.
Both Levine and fellow sprinter James Ellington were injured in a road accident in Tenerife in January.
The pair were on a warm weather training camp when they were involved a head-on collision while riding a motorbike.
Levine broke his pelvis and therefore missed the entire 2017 track season.
He has returned to training, however, and had been working with British Olympic sprint legend Linford Christie's sprint group at Brunel University London.
Ellington underwent surgery to repair broken bones in his tibula and fibula and also fractured his pelvis.
Levine is no longer coached by Christie, who in 1999 was found guilty of using the anabolic steroid nandrolone following a positive test at a meeting in Germany.
He is also no longer a client of Christie's management consultancy Nuff Respect.
It is understood, however, that Levine uses Robert Wagner, the man at the centre of the latest Justin Gatlin controversy, as a race agent.
Both Gatlin, the world 100 metres champion, and Wagner have denied any wrongdoing.
Undercover reporters from The Daily Telegraph recently contacted Wagner and Dennis Mitchell, Gatlin's coach, about obtaining human growth hormone and testosterone.
Wagner was filmed allegedly claiming he could supply drugs and Mitchell is alleged to have spoken about "complex" designer drugs which are unknown to the authorities and do not show in drugs tests.
Wagner is also quoted as having named sport stars using drugs, including both Gatlin and Mitchell.
He has since claimed he invented the story about obtaining banned drugs in a bid to impress the undercover reporters.
Levine was a member of the British men’s 4x400m squad at the Rio 2016 Olympic Games but did not run, although he did compete in the event four years earlier at London 2012, where the team placed fourth.
He claimed 4x400m relay gold at the 2014 European Championships and 2013 European Indoor Championships.
World Indoor Championships 4x400m relay silver medals were won by Levine in 2012 and 2014 and he secured bronze in 2010.