South Africa's top track official has apologised for denying knowledge of gender tests done on runner Caster Semenya in South Africa.

Athletics South Africa president Leonard Chuene told reporters Saturday that his constant denials were an "error of judgment" and apologised for misleading the public. He says he knew of the tests and was trying to protect Semenya's privacy.

South African officials have repeatedly said tests were done on the 800-meter world champion only abroad.

The international athletics body ordered gender tests after questions arose about Semenya's muscular physique and stunning improvement.

It has refused to confirm or deny Australian media reports saying tests show Semenya has both male and female organs. - Sapa-AP