TOULOUSE, France (Reuters) - French police were hunting four men on Thursday who allegedly raped a woman outside a nightclub in Toulouse after images of the apparent attack circulated on social media, the prosecutor’s office said.

The incident occurred on Saturday night in a suburb of Toulouse in southwestern France. The local prosecutor has opened an investigation into the case and into the recording of it.

“We’re looking for four people, perhaps more,” the Toulouse prosecutor’s office said. “No arrests have been made so far.”

The alleged victim, who is 19 years old, told police on Wednesday that she had been attacked in the nightclub’s car park and that she believed she had been drugged. Blood samples from the teenager were being analyzed, the prosecutor’s office said.

Video of the attack was circulated on Snapchat and Twitter, French media reported.

At one point in the recording, according to French media, a voice can be heard warning the others: “Stop filming, it’s a rape ... It’s a rape, it’s a rape.”

Social media users raised the alarm via the interior ministry’s Pharos portal, a site where internet users can report illicit online content. Police blocked the videos and urged people not to share footage showing non-consensual sexual acts.