By Daphne Psaledakis, David Lewis and Nafisa Eltahir WASHINGTON/NAIROBI/CAIRO (Reuters) -The United States determined on Tuesday that members of Sudan's Rapid Support Forces (RSF) and allied militias committed genocide in Sudan and imposed sanctions on the group's leader over a conflict that has killed tens of thousands of people and driven millions from their homes.

A force fighting Sudan’s army in a brutal civil war committed massacres and rape that amount to genocide, the Secretary of State said, two decades after a finding of genocide in the same region.

Sudan’s Rapid Support Forces has used systematic murder and sexual violence in its war in Sudan, the U.S. government says as it sanctions RSF’s chief, Hemedti.