Three Grenoble rugby union players have been put under formal investigation by a French magistrate on suspicion of gang rape following a complaint by a 21-year-old woman, a judicial source said.
Earlier, prosecutors issued a statement saying there was evidence that France's Loick Jammes, New Zealand's Rory Grice and Ireland's Denis Coulson had probably taken part "either as initiator or accomplice" in the crime.
The woman told police on March 12 that she had been drugged and taken to a hotel in Bordeaux where she was raped after a French league game between Bordeaux and Grenoble.
Being placed under formal investigation in France is often the first step to a trial but it does not necessarily mean that the case will go to court.
The three players were not thought to have been held in custody, but have been placed under restrictions which will require them to report regularly to French police until the case is resolved.
Last month, a lawyer for Coulson denied the allegations and described the incident "as a night out between consenting adults".
