Gang networks that traffic Nigerian women and girls to the Ivory Coast and force them into prostitution, should be investigated and shut down, urge campaigners.
Last month Human Rights Watch met 30 Nigerian women in different Ivory Coast towns believed to have been trafficked for sex work.
Scores of similar cases involving Nigerian women and girls were reported by Ivory Coast officials, said the United Nations and Nigerian embassy staff.
Many victims were 15 and 17-year-olds or had been children when they arrived in the west African country.
"These women and girls were sold dreams of migrating to better their lives, but then found themselves in a personal hell," said Human Rights Watch spokesperson, Corinne Dufka. "The Ivorian and Nigerian authorities need to find and prosecute the perpetrators, work with regional neighbours to shut down their operations, and do more to protect the victims."
A police official estimated that at least 100 Nigerian women were working as prostitutes in just one Ivory Coast town. Most of them were likely to have been trafficked.
All of the women and girls interviewed told how they were tricked into leaving their homeland with promises of work as trainee hairdressers or tailors, or in Europe. They said they were recruited by Nigerian women and sent through Benin, Togo, Ghana, and Burkina Faso.
Staff at the Nigerian embassy in the former Ivory Coast capital, Abidjan said they had repatriated scores of women trafficked for prostitution, including dozens this year alone, and warned that the problem is growing.
"I came here six years ago with five other girls from Delta State,” said Ruth* a 27-year-old Nigerian woman trafficked for prostitution in the central Ivory Coast: “The woman who brought us told me that she sold wrappers [fabric used as a skirt] in Côte d'Ivoire,” she told Human Rights Watch. “I thought it was a good opportunity for me to learn a business, so I left Nigeria and went with her. The second day, she handed us each a condom and said, ‘this is what you are going to do.' What could I do? I had nobody backing me ... so I did it."
Many of the women were told that they would have to work to pay off debts worth thousands that had been spent on their travel. Others believed that bad things would happen to their families, if they came forward.
"Nigerian and Ivorian authorities must more proactively combat those who prey on vulnerable girls and women," said Ms Dufka. "Many more will be trafficked for prostitution if governments fail to take action."
(*not her real name)