Mo Farah missed two drugs tests a year before the London 2012 Olympics, Sportsmail can reveal.

At a time when the British distance runner's controversial American coach Alberto Salazar and training partner Galen Rupp are facing a series of allegations, Farah's own problems with the doping authorities reached a peak only a few months after he started training under Salazar in February 2011. The two missed tests put his participation at the 2012 Olympics, where he won two gold medals, at risk.

UK anti-doping rules state an athlete who misses three tests in any 12-month period (down from 18 months since 2013) can face up to a four-year ban. Britain's Christine Ohuruogu was suspended for 12 months in 2006 after missing three tests and falling foul of the World Anti-Doping Agency's 'whereabouts' system, which forces athletes to pick an exact location for one hour every day in case they are needed for testing.

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Mo Farah posted a picture on Twitter, saying: 'Good to be out on the track in France today, getting ready for my next race in Monaco!! Focusing on my training!!!!'

A jubilant Farah wins the men's 5,000m at London 2012, the first of his two Olympic gold medals

Farah's first missed test appears to have occurred in early 2010, several months before the double Olympic champion teamed up with Salazar and six months before he broke David Moorcroft's 28-year-old British 5,000m record and became the first Briton to break the 13-minute barrier.

But the second test seems to have been scheduled once Farah started working with Salazar. It should have taken place at Farah's home in Teddington, London, but the athlete appealed to the UK Anti-Doping Agency, claiming that he did not hear his doorbell.

As part of his appeal, Farah's agent Ricky Simms submitted video evidence filmed in Farah's house in which he tried to show that it was difficult to hear the doorbell from his client's bedroom. UK Anti-Doping lawyers dismissed it as evidence. Simms also voiced his unhappiness at UK Anti-Doping, claiming they were 'unreasonable' and didn't want to help Farah.

'I can understand why your client remains frustrated, but that really is born out of the fact that he feels he is being punished for something that he did not intend to do,' UKAD's lawyers told Farah's legal team in an email on June 9, 2011.

'Intent and negligence are not the same thing, though, as I am sure you have advised him. The simple fact with this Missed Test is that your client says that he did not intend to miss the test, but it is clearly his own fault that he did.'

In the email, UKAD added: 'We cannot 'suspend' the Second Missed Test'. In a final remark UKAD said: 'We remain of the view our collective efforts are best directed to ensuring that no further whereabouts issues arise between now and the 2012 Games.'

Farah kneels as he waits to hear that he has broken David Moorcroft's 5,000m British record in Zurich

Farah joined Salazar's set-up in 2011 and has lived in the US, training at the Nike Oregon Project since

THE QUESTIONS WE PUT TO FARAH These are among the questions we asked Mo Farah and his agent Ricky Simms. They did not respond. 1 Can you give the exact date and circumstances of the first test and explain why you missed it? 2 And the same for the second missed test... 3 As you will be aware, missing a third test would have meant you were banned from athletics. How did you react to this prospect in the year before London 2012? 4 Have you missed any further tests? 5 We are aware that you challenged UK Anti-Doping over the fairness of the second test. Can you explain why? 6 Are you satisfied with the responses you have received from Alberto Salazar in respect of the doping allegations to the point where you are happy to continue being coached by him? 7 Have you contacted the former Nike Oregon Project runners who have given evidence to the US Anti-Doping Agency? 8 Do you respect the WADA code and adhere to their regulations in pursuit of drug-free sport? Advertisement

Farah was concerned that he could be hit with a sanction, judging by the correspondence between lawyers, Farah and Salazar in May and June 2011 seen by Sportsmail.

As Salazar warned Farah on May 5 that year: 'If you miss another test, they will hang you.'

Farah won his first world title in the summer of 2011, storming to 5,000m gold in Daegu. He also set a new British and European record for 10,000m of 26min 46.57sec, and lowered his British 5,000m mark to 12min 53.11sec. Both times remain his personal bests. But Farah was living dangerously. As his legal representatives told UKAD in an email on June 8, 2011: 'A possible Third Whereabouts Failure still is a spectre haunting him today.'

The same lawyer added: 'As Mr Farah's recent successes have raised his hopes for the upcoming Olympic Games, I hope you can understand his frustration regarding the Second Whereabouts Failure.'

Sportsmail sent Farah's agent a list of questions in the hope of securing a detailed explanation for the two missed tests. Simms remained silent.

Farah seems now to be keeping his distance from Salazar, posting pictures of himself training in Font Romeu, France. He is likely to stay in the Pyrenees until he competes at the Monaco Diamond League meeting on July 17.

Salazar is still believed to be in Oregon, where the heat has been rising in recent weeks. On June 3, BBC Panorama made a series of allegations against him and Rupp. Among them, it is alleged that Salazar put Rupp on testosterone medication at the age of 16.

Farah finishes ahead of training partner Galen Rupp (left) to add the 10,000m Olympic crown to his haul

Rupp, Salazar and Farah pose after the 10,000m at a deserted Olympic Stadium in East London

Salazar denied 'all allegations of doping' and said he would prove witnesses had made 'false statements'. American Rupp, who finished second to Farah in the 10,000m at the 2012 Olympics, also denied the allegations. But there are now thought to have been 17 witnesses linked to the Salazar-run Nike Oregon Project who alleged the misuse of prescription drugs.

That was followed by revelations from Sportsmail that witnesses had seen unmarked vials of a clear, unidentified liquid and needles at two of Salazar's altitude training camps in 2008 and 2011.

John Stiner, a sports massage therapist employed by Salazar for an altitude training camp in Park City, Utah, in June 2008, told US Anti-Doping that he found vials in the fridge and a bag of unused hypodermic needles in the bathroom of one of the apartments Salazar and Rupp rented. Stiner also said Salazar told him he would find a tube of testosterone gel in his room.

Stiner claims Salazar asked him to send the items to his home in Portland. He kept what he says was the shipping receipt for $150.

Three years later in July 2011, Rupp was in France training with Farah and others from UK Athletics at a camp also attended by Steve Magness, a young American coach and one-time assistant to Salazar.

Magness has also made allegations to US Anti Doping, claiming he found an unmarked vial in France that belonged to Rupp. Magness says he was in a hire car with another athlete from the Nike project, Australian distance runner Jackie Areson, driving to the airport where they intended to return the car when they found the vial.

John Stiner claims he found vials of clear liquid and bags of needles at a Salazar training camp in Utah

Salazar, who is believed to be in Oregon, is pictured last month at the Prefontaine Classic track and field meet

The allegations against his coach have put Farah under pressure. He left the Aviva Grand Prix in Birmingham 11 days ago without competing and said he would demand proof from his coach that he was not guilty of any doping violations.

Farah added that he would only remain with Salazar if he was satisfied his coach was clean.

Sportsmail asked him if he had received such assurances, but again there was no response.

UK Anti-Doping (UKAD) refused to comment on allegations of the missed drugs tests, saying: 'UK Anti-Doping does not disclose personal data relating to an individual's test history.

'UKAD has a dedicated Athlete Support Officer who works with athletes on the National Registered Testing Pool, and with National Governing Bodies of sport, to ensure they manage their whereabouts reporting responsibilities.'

HOW THE TESTERS ARE TRYING TO KEEP THE SPORT CLEAN by MARTHA KELNER

How does drug testing work in athletics?

As an Olympic event, athletics is signed up to the World Anti-Doping Agency (WADA) code. Tests are carried out in one of two ways: in competition or out of competition.WADA define in-competition testing as ‘the period commencing 12 hours before competition... through to the end of such competition and the related sample-collection process.’ Out-of-competition testing is generally deemed to be more effective as little or no advance warning is given.

Are athletes tested after every race?

No. But all those who set world records, all winners and most podium finishers will be tested after a race at a major championship.

Athletes are not tested after every race but world records breakers, all winners and most podium finishers will

How many times is an athlete tested per year?

Mo Farah’s figures from the International Association of Athletics are available online: he had ‘1-3’ tests in 2010 and the same in 2011. Usain Bolt had ‘4+’ in each year. Both athletes will have had UK Anti-Doping (UKAD)/WADA tests on top of that.

Is it pot luck how often athletes are tested?

If there is intelligence, for example suspicions about a certain athlete or training group, testers can carry out targeted testing.

How do testers know where athletes will be if they’re not competing?

All athletes are required to give anti-doping authorities their ‘whereabouts’, a general picture of where they will be for the next three months. That includes training camps or activities on certain days of the week. A specific one-hour location each day, between 5am and 11pm, is also required.

How do athletes give this information?

The Anti-Doping Administration and Management System (ADAMS) is an online database which, among other things, allows athletes to list their whereabouts from anywhere in the world. An athlete can also nominate an authorised representative, such as a team manager or agent, to submit this information on their behalf.

Farah (left) had 1-2 tests in both 2010 and 2011 whereas Jamaican sprinter Usain Bolt (right) had four or more

How late can athletes change information?

If there is a last-minute or emergency change to their whereabouts, athletes can text or email up to one minute before the start of their specified time slot.

What happens if an athlete keeps changing the details of their whereabouts?

Repeated last-minute changes may be investigated.

What if an athlete forgets to notify of a change of whereabouts?

When an athlete has failed to be available for testing on any given day at the location and time they specified — or are not where they said they would be — they will be deemed to have missed a test.

What if they are abroad?

If an athlete is travelling overnight they can create a ‘travel entry’ on ADAMS but will need to enter details of their journey (such as airline carrier and flight number). When staying in another country, they can be tested by that country’s national anti-doping agency. In the US for example, he or she would be subject to the US Anti-Doping Agency.

What if they are staying in a hotel, or at somebody else’s house?

They must change their ‘overnight’ location on the system.

What happens if an athlete misses a test?

They receive one strike for each missed test. Any combination of three missed tests or filing failures within a 12-month period amounts to an Anti-Doping Rule Violation.

What is the punishment for missing three tests?

The punishment for missing three tests within 12 months is a two-year ban, although an athlete can get a reduction if he or she has ‘substantial proof that they were not at fault or intending to cheat’.

Great Britain's Christine Ohuruogu was suspended for 12 months in 2006 after missing three tests in a year

What happens during the testing process?

The athlete is asked to provide a urine sample of 90ml in front of the doping officer or an official witnessing chaperone. When ready to provide the sample, they are given a collection vessel (resembling a test tube). In order for the officer or chaperone to have a clear view of the sample being provided, the athlete is asked to pull up their shirt to mid-torso and pants down to mid-thigh. The doping officer then asks the athlete to pour 30ml from the 90ml sample into a tube marked sample ‘B’ and the rest into a tube marked sample ‘A’. They then tell the athlete to secure the lid.

Are they blood or urine tests?

Out-of-competition tests are more often urine tests but can also be blood tests.

How many testers come knocking at your door?

Usually just one Doping Control Officer, who will be of the same gender as the athlete.

Does blood test collection differ?

During the blood-collection process, less than one tablespoon of blood will be drawn and the amount of blood should not affect an athlete’s performance. An athlete is required to remain seated for a minimum of 20 minutes prior to the blood draw.

Can athletes ask for other people to be there?

Yes, the athlete’s representative can sit in.

What happens to the samples?

The athlete will seal the sample then select a collection box which they are satisfied has not been tampered with.

It is then transferred to the doping control station to begin testing.

What happens if the ‘A’ sample is positive?

The athlete, the national governing body and the international federation (the IAAF) will be notified. The athlete will have the opportunity to be present for the ‘B’ sample opening.

What is the sanction for a first failed test?

It varies depending on the severity of the offence/substance involved but can be a ban of several years.

What if you don't mean to take a banned substance?