Powell’s agent Paul Doyle confirmed in an email to Press Association Sport that the former 100 metres world record holder had tested positive for a banned substance.
Powell, 30, has won gold medals in the 4x100m relay at the Olympics and World Championships and held the world record before his compatriot Usain Bolt.
> Ben Johnson (Athletics)
> Marion Jones (Athletics)
> Justin Gatlin (Athletics)
> Lance Armstrong (Cycling)
> Floyd Landis (Cycling)
> Alberto Contador (Cycling)
> Shane Warne (Cricket)
Flashback: When sexy models sizzled in bikinis at Tokyo fashion show
Photos: Amy Jackson, Daisy Shah at Mumbai airport
Photos: Sridevi, Irrfan and other celebs at 'Mughal-e-Azam' screening
Photos: WWE Diva Kelly Kelly sizzles in bikinis on Instagram
Photos: Parineeti Chopra celebrates birthday with fans