Amnesty International on Tuesday called on the authorities in Egypt to bring to justice those responsible for forced virginity tests on female protesters, slamming it as "nothing less than torture."
The London-based rights group's statement comes after an apparent admission by an army general to CNN that women detained on 9 March in Cairo had been subjected to virginity tests.
But a senior military official on Tuesday denied to AFP reports that the army had conducted such tests, saying "these allegations are baseless."
The general, speaking to CNN on condition of anonymity, had defended the practice.
"We didn't want them to say we had sexually assaulted or raped them, so we wanted to prove that they weren't virgins in the first place," he told the US broadcaster.
"The girls who were detained were not like your daughter or mine," the general said.
"These were girls who had camped out in tents with male protesters in Tahrir Square, and we found in the tents Molotov cocktails and (drugs)," he said.
Amnesty condemned the admission as "an utterly perverse justification of a degrading form of abuse."
"The women were subjected to nothing less than torture," it said.
Authorities "must bring those responsible for ordering or conducting forced 'virginity tests' to justice.
"This general's implication that only virgins can be victims of rape is a long-discredited sexist attitude and legal absurdity. When determining a case of rape, it is irrelevant whether or not the victim is a virgin."
In March, Amnesty collected testimonies of women after it said army officers used force to clear Cairo's Tahrir Square, the focus of the uprising that forced Hosni Mubarak to resign in February, and detained at least 18 women.
Women protesters said they were beaten, given electric shocks, subjected to strip searches while being photographed by male soldiers, then forced to submit to "virginity checks" and threatened with prostitution charges, Amnesty said.
In Cairo, the military official told AFP that "all legal measures would be taken regarding what was published because it is based on false information."