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.

The United States has accused Sudan's paramilitary Rapid Support Forces and proxy militias of committing genocide in the Northeast African nation's nearly 2-year-old civil war.