The international criminal court (ICC) in The Hague has previously launched investigations into the alleged use of systematic rape as a weapon against the civilian population by leaders of the Lord's Resistance Army in Uganda and militia groups in the Democratic Republic of the Congo and the Central African Republic.
But the claim by the ICC's chief prosecutor, Luis Moreno-Ocampo, that the impotency drug Viagra was distributed to Libyan troops as part of an official policy of rape is unprecedented.
The former Congolese vice-president Jean-Pierre Bemba is facing charges that he unleashed his soldiers to commit rape, murder and pillage in the Central African Republic in 2002-03. He has pleaded not guilty. The landmark case will define a commander's legal responsibility to control his troops wherever they are in the world.
Under the ICC's code, multiple rapes constitute a crime against humanity alongside murder, enslavement, forcible transfer of populations and torture.
The international criminal tribunal for the former Yugoslavia also tried suspects for alleged mass rape of detainees during the Bosnian conflict.
It had difficulties securing prosecutions in some cases because it could not show there were enough victims to constitute an attack on a civilian population.
Moreno-Ocampo has already requested arrest warrants against Muammar Gaddafi, his son Saif al-Islam and the country's spy chief, on other charges of crimes against humanity allegedly committed during attempts to crush the country's rebellion.
That request is being considered by ICC judges. Any mass rape allegations adopted by the court would be added to the indictment as fresh charges.
The rape allegation against Gaddafi has already been raised in the UN security council. In April the US ambassador, Susan Rice, said some Libyan troops had been issued with Viagra.
Moreno-Ocampo said the question until recently had been whether Gaddafi himself could be associated with the rapes "or is it something that happened in the barracks?"
"But now we are getting some information that Gaddafi himself decided [to authorise the rapes] and this is new.
"It never was the pattern he used to control the population. The rape is a new aspect of the repression. Apparently he decided to punish using rapes."
The chief prosecutor said there was evidence of Libya acquiring "containers" of such drugs "to enhance the possibility to rape women".
He said it was difficult to know how widespread the rape was but he had received information there were several hundred victims in some areas.
