A human rights group says women who fled violence in Sudan's Darfur region continue to deal with rape and sexual assault at a refugee camp in Chad.
The group, Physicians for Human Rights, says it interviewed 88 women from Darfur at the Farchana refugee camp in November.
It says 29 of the women, about a third, made "confirmed or highly probable" accusations of rape. Three of the women were assaulted twice.
The group says about slightly more than half the rapes happened in Darfur, with the rest occurring in Chad.
Many of the rapes in Chad occurred when women left the refugee camp to look for firewood. Physicians for Human Rights called for rape to considered a war crime.
The issue is a contentious one for the Sudanese government, which has denied that systematic rape or violence against women ever took place.
The International Criminal Court has accused Sudan's president, Omar al-Bashir, of organizing a campaign of rape, murder, and other crimes against Darfur civilians.
Sudan's government has been fighting rebels in Darfur since 2003.
The fighting and related violence has driven hundreds of thousands of refugees across the border into Chad.
Some information for this report was provided by AP.