A view of destruction in a livestock market area in al-Fasher, the capital of Sudan s North Darfur state on September 1, 2023 . AFP
At the same time, the State Department announced $163 million in new humanitarian assistance to help victims and refugees of Sudan's nearly five-month-old civil war.
The US Treasury sanctioned RSF senior commander Abdelrahim Hamdan Daglo and the brother of Mohamed Hamdan Daglo, leader of the paramilitary RSF.
Under Abdelrahim Daglo, the Treasury said, RSF members "have engaged in acts of violence and human rights abuses, including the massacre of civilians, ethnic killings, and use of sexual violence."
It said that many of the abuses took place in the Darfur region of Sudan.
The US State Department meanwhile placed RSF general and West Darfur sector commander Abdul Rahman Juma on its blacklist for what it called "his involvement in a gross violation of human rights."
"According to credible sources, on June 15, 2023, RSF forces led by General Juma kidnapped and killed the governor of West Darfur, Khamis Abbakar, and his brother," the State Department said.
It said the murder came just hours after Abbakar publicly condemned the RSF.
The sanctions came as the Sudanese Armed Forces and the Rapid Support Forces continued to fight for control of the country.
Repeated efforts by outside groups have failed to produce a durable ceasefire between the two sides, led by rival generals.
US Treasury sanctions generally aim to make it harder for blacklisted persons or businesses to operate internationally by forbidding Americans or US-based businesses -- including foreign banks with US branches -- from transactions with them.
They also freeze any assets the targeted person has under US jurisdiction.
The State Department's action places US visa restrictions on Juma.
Separately, while visiting Chad, US Ambassador to the United Nations Linda Thomas-Greenfield announced $163 million in aid to help people affected by the civil war.
The State Department said more than 24.7 million people in Sudan need humanitarian assistance.
Some 3.6 million have been forced to flee their homes to other parts of Sudan for avoid the war.
Another one million have fled Sudan into neighboring countries, the State Department said.