More than 20 women prisoners were raped after a riot broke out in a jail in the southeastern Democratic Republic of Congo in September, investigators said Tuesday.

The French station Radio France Internationale (RFI), which broke the story, said some of the women were raped for days by male convicts after prison authorities lost control of the facility.

The riot erupted in a prison in Lubumbashi on September 25 as the city was attacked by a militia group.

Public prosecutor Teddy Katumbo Lumbu told AFP: “According to the prison governor, all the women there were raped. There were about 50 of them.”

He said he had dispatched investigators to the jail.

Of 25 women who had spoken to his team in early October, “21 said they had been the victim of rape, one of whom was a minor,” he said.

Fifteen prisoners have been charged with rape, arson, property damage and other crimes, he said.

RFI said the women were “regularly raped over three days, some of them by around 20 inmates. Their ordeal ended only when the authorities recovered control of the prison on September 28.”

Chantal Yelu Mulop, President Felix Tshisekedi’s special advisor on sexual violence, told the radio station that the victims had been unable to get “medical, legal and psychological help.”

A doctor who went there to provide help did not have enough supplies to help them, she said.

Timothee Mbuya, head of a DR Congo campaign group called Justicia, said some women “are suffering from abdominal pains, and others are still bleeding.”

The riots broke out after “heavily-armed men” attacked the jail, prison governor Pelar Ilunga said at the time.

The attack occurred when a militia group, from a separatist group calling for the independence of the surrounding Katanga region, raided Lubumbashi.

Around 20 people died in the violence, including two policemen who were decapitated, provincial officials said at the time, while Ilunga said four prisoners were killed when they tried to break out of the jail.