British Cycling has launched an investigation after it emerged that a soigneur who allegedly injected American teenagers with steroids without their knowledge was working around young British riders as recently as 2016.

Angus Fraser was named in a deposition in a case settled out of court in the United States in which he was alleged to have administered performance-enhancing drugs to former US junior cyclists in 1990 without their knowledge or consent. The Scotsman was also said to have injected riders on the British team ANC-Halfords with unknown substances in the 1980s.

The Guardian understands Fraser has since made attempts to change his name to Kris Tolmie. He was able to get accreditation under the name Angus Fraser as a “helper” – a category usually reserved for mechanics and soigneurs – to attend the London Six Day event in 2015. It is thought he was working with Revolutions Racing, a team based in Shrewsbury. At the event, held in the Olympic velodrome, he was pictured in the track centre with Mark Cavendish as well as next to two young Danish riders.

At the Gent Six Day in 2016 he was pictured on a massage bed sat next to the rider Chris Lawless, a product of the British Cycling development programme who currently represents the UCI Continental team Axeon-Hagens Berman and was aged only 21 at the time. There is no suggestion Fraser or any British rider was contravening anti-doping laws in any way but British Cycling admitted having someone with his reputation exposed to young riders would be concerning.

A British Cycling spokesman said: “As soon as this matter was bought to our attention we contacted the club and then the relevant authorities – UK Anti-Doping and the NSPCC’s Child Protection in Sport Unit. There is absolutely no place in our sport for doping or for those who take advantage of vulnerable people. We are working to establish the facts and are ready to quickly take any appropriate action.”

It is understood Usada, UKAD and the CPSU have told British Cycling that that they hold no information relating to Fraser. Nor has it found evidence of him working in an official capacity with young people for British Cycling. The investigation is ongoing.

Stephen Swart, a New Zealand cyclist who rode for the British team ANC-Halfords in the 1980s, said in the book Seven Deadly Sins – about Lance Armstrong’s demise – that the riders were all rounded up and injected with an undetermined substance by Fraser. “We had complete confidence in this guy because we thought he knew what he was doing. Like if you go to the doctor when you are sick, you have confidence in him.

“You think it can’t be very bad since it doesn’t test positive. And I wasn’t a big enough cyclist to have the right to ask questions. I remember two cyclists from the team who carried their own briefcases and it wasn’t papers that they carted around with them.”

In 2006, USA Cycling paid two former junior cyclists $250,000 (around £194,000) to settle out of court after they alleged Fraser and their junior national team coach, René Wenzel, administered performance-enhancing drugs to them without their knowledge or consent.

Greg Strock and Erich Kaiter claimed Fraser and Wenzel injected riders with cortisone, treated them with other steroids and provided them with amphetamines and other drugs on several occasions during the 1990 season.

Both Strock and Kaiter, who was later diagnosed with Crohn’s disease, said the combination of drugs left them with suppressed immune systems and masked symptoms of what otherwise would have been easily treated illnesses.

Fraser could not be reached for comment.