Caster Semenya wins women 's 800m gold at World Athletics Championships . South African secures victory after IAAF asked for gender test on the teenager . Ethiopia 's world indoor champion Deresse Mekonnen claimed a surprise silver with defending champion Bernard Lagat , also Kenyan-born but now competing for the United States , in bronze . Comment:
Caster Semenya wins women 's 800m gold at World Athletics Championships . South African secures victory after IAAF asked for gender test on the teenager . Comment: