Reigning world 800m bronze medalist Kipyegon Bett has been banned for four years for using Erythropoeitin (EPO).
Bett, the former world under 20 800m champion received the ban by IAAF Athletics Integrity Unit on Friday.
The world under 18 800m champion had refused to allow his urine sample to be taken in February and then in July, when a sample was taken, he tested positive for the prohibited substance EPO, an endurance-boosting hormone, the integrity unit said.
The AIU handles integrity and doping issues for the International Association of Athletics Federations (IAAF).
Bett is the latest Kenyan to fail a drugs test. A World Anti-Doping Agency (WADA) report said between 2004 and Aug. 1, 2018, as many as 138 athletes from the east African nation tested positive for banned substances, 113 in competition.