Usain Bolt declares 'I'm clean' July 25, 2013 -- Updated 1624 GMT (0024 HKT) Usain Bolt returns to the scene of his London 2012 Olympic triumph this weekend. Usain Bolt tells reporters "I'm clean" ahead of London Diamond League meeting Tyson Gay and Asafa Powell failed drugs tests earlier this month Gay and Powell both deny knowingly taking banned substances A Jamaican international footballer fails a drugs test during a World Cup qualifier (CNN) -- Usain Bolt has a simple message following a string of doping scandals that have cast a shadow over athletics and Jamaican sport: "I'm clean." A six-time Olympic gold medalist, Bolt was speaking publicly for the first time since his fellow Jamaican and elite sprinter Asafa Powell and Tyson Gay of the United States tested positive for banned substances. "If you were following me since 2002 you would know that I have been doing phenomenal things since I was 15," the 100 meter and 200 meter world record holder told reporters ahead of this weekend's Diamond League meeting in London. I was the youngest person to win the world junior title at 15, I ran the world junior record at 18, the world youth record at 17. I have broken every record there is to break, in every event I have ever done. For me, I have proven myself since I was 15. For me, I have shown I was always going to be great. Read: 'Athletics can learn from cycling' I was made to inspire people and to run. I was given a gift and that's what I do. I'm confident in myself and my team, the people I work with. And I know I am clean. Powell became the second high-profile Jamaican sprinter to fail a drugs test in a matter of weeks. Veronica Campbell-Brown, a a triple Olympic gold medalist, was given a provisional suspension in June. Powell, Campbell-Brown and Gay deny knowingly taking banned substances, as does Jamaican Sherone Simpson who also tested positive. Blog: Lifetime bans the only way to deter dopers? Bolt revealed he had sent a text message to Powell, telling his compatriot "to stay strong and focused." "There are a lot of details yet to be discussed so I'm just sitting and waiting to see the results and what's what," added Bolt. There are a lot of things that haven't been done and haven't been said so I'm just waiting to see what is going on. You have to be very careful as an athlete because right now there are a lot of things on the banned list. You have to keep up to date all of the time. It's hard but that's why you have a team to help you out with this kind of thing. Away from athletics, Jamaican sport was rocked by a fresh doping scandal after one of the Caribbean nation's footballers become the latest sporting figure to fail a drugs test. The unnamed footballer failed a test carried out by the sport's global governing body FIFA following last month's World Cup qualifying match against Honduras. "During the World Cup Qualifying match, Honduras vs Jamaica, on June 11, 2013 a member of the Jamaican squad returned an adverse analytical finding on his urine sample," read a statement from the Jamaican Football Federation (JFF). The testing was carried out by the FIFA. This means that the ensuing process will be managed by the FIFA. The player has been informed and we await further information from the FIFA. The JFF has taken this matter very seriously and a thorough investigation has already started by the chairman of the JFF Medical Committee.