Sexual violence and rape of women and girls in the western Sudanese region of Darfur should be considered a war crime, Pamela Shifman, a United Nations Children's Fund (UNICEF) adviser on violence and sexual exploitation, was reported as saying on Tuesday. "The perpetrators must be held accountable. There are Sudanese laws against rape and there are Sudanese courts, and they have to be used," Shifman, who visited the region last week, said.