Athletes that failed drug test are the 400m runner Joyce Zakary and the 400m hurdler Koki Manunga. Both athletes have accepted provisional bans after "targeted tests" by the IAAF.
Zakary who set a new NR of 50.71 seconds in the 400m heats on Monday and Manunga who finished sixth in her heat with a time of 58.96 were tested at their team hotel on 20 and 21 August.
Zakary who qualified for the 400m semi final did not show up to the start line on Tuesday.
"Athletics Kenya (AK) has already met with the IAAF and the athletes involved, and has begun investigating the situation which led to these results," said Athletics Kenya. "Follow-up action will be taken in Kenya."