Mo Farah was questioned by a United States Anti-Doping Agency investigator on Saturday over the doping allegations surrounding his coach Alberto Salazar.

The double Olympic champion was questioned by American lawyer Bill Bock, the man who helped bring down Lance Armstrong, for five hours at the Grange Tower Bridge Hotel, the Sunday Mirror reported.

The meeting was routine and had been scheduled for some time.

The 32-year-old, one of a number of people the anti-doping authorities are talking to, has already said he is happy to co-operate with any investigation.

Farah has not been accused of any wrongdoing, but has been caught up in the doping storm which has engulfed Salazar who has vehemently denied breaking anti-doping rules.

Farah’s questioning by USADA came the day after he was cheered to the rafters on his return to the Olympic Stadium, winning over 3,000 metres at the Sainsbury’s Anniversary Games, his first race in Great Britain since the doping scandal broke.

The Briton, who is sticking by his under-fire coach but has vowed to leave him should any accusations be proven, told the Sunday Mirror after the meeting: “It went alright... It’s all good.”

Farah paid tribute to the raucous support he received from the Olympic Stadium crowd on Friday.

He said: “It was amazing to get the support I got, it was incredible, it just reminded me of 2012.”

Farah also received the backing of Usain Bolt in the week.

“I’ve come through the ranks with Mo, so I’ve seen the work that he’s put in,” he said.

“For me I’m sorry for Mo, because every day I hear in the papers they’re trying to tear him down. I think he works so hard.”