A leading human rights group called Friday on the United States and the United Nations to impose further sanctions on those in Sudan “responsible for the atrocities” in the troubled Darfur region, where evidence of scorched-earth attacks is mounting.

The northeast African country plunged into chaos in April when monthslong tensions between the military, led by Abdel Fattah Burhan, and the paramilitary Rapid Support Forces, commanded by Mohammed Hamdan Dagalo, exploded into open fighting in the capital of Khartoum, and elsewhere. In Darfur, the scene of genocidal war in the early 2000s, the conflict has morphed into ethnic violence, with the RSF and allied Arab militias targeting African communities in the western region, U.N. officials say.

In a press release, Human Rights Watch said Washington should impose targeted sanctions to “ensure that the U.N. Security Council finally acts to protect civilians and to hold those responsible for the atrocities to account.” The U.S. took over the rotation presidency of the U.N. Security Council on Aug. 1.

The New York-based watchdog group said at least seven villages and towns have been almost completely burned to the ground or destroyed in West Darfur alone, according to satellite footage and testimonies analyzed by the group. These include Habilla Kanari, Mejmere, Misterei, Molle, Murnei, Gokor, and Sirba.

“The world should not stand by as town after town in West Darfur is burned to the ground, sending tens of thousands of civilians fleeing for their lives,” said Tirana Hassan, executive director at HRW.

In June, the U.S. imposed sanctions against four key companies either linked to or owned by the warring factions. The White House also placed visa restrictions on army and RSF officials, and leaders from the former government led by ousted President Omar al-Bashir. It did note specify which individuals were affected.

Al-Bashir, who ruled Sudan for more than 30 years, is wanted by the International Criminal Court on charges of war crimes and genocide linked to the Darfur conflict.

Later Friday, the U.S., Britain and Norway called in a joint statement for an end to the bloodshed in Darfur. The three countries condemned the ongoing violence, “especially reports of killings based on ethnicity and widespread sexual violence by the Rapid Support Forces” and allied militias.

Since the latest fighting erupted in mid-April, there have been at least nine temporary cease-fire agreements between the military and the RSF, most of which were brokered by Washington and Riyadh during cross party talks in the Saudi coastal city of Jeddah. However, all the truces foundered.

Last Month, Karim Khan, a prosecutor from the ICC, told the United Nations that he would be investigating alleged new war crimes and crimes against humanity committed in Darfur.

Earlier this week, the rights organization Amnesty International separately accused both warring parties of committing extensive war crimes, including deliberate killings of civilians and mass sexual assault. Amnesty said almost all rape cases were blamed on the RSF and its allied Arab militias.

In its 56-page report, Amnesty said the RSF abducted 24 women and girls — some as young as 12 — and held them “for several days during which they were raped by several RSF members.”

The now nearly four-month conflict in Sudan has killed more than 3,000 people and wounded more than 6,000 others, according to the last government figures, released in June. The true tally is likely much higher, according to doctors and activists.

Meanwhile, the fighting has forced 4 million people to flee their homes either to safer areas inside Sudan or to neighboring countries, according to figures from the U.N. migration agency.

The U.N. Food and Agriculture Organization, or FAO, said on Thursday that 20.3 million people in the country now “face severe hunger,” double the number from the same time last year.