CAIRO — Tribal clashes between Arabs and non-Arabs in Sudan's war-ravaged Darfur region Sunday killed 168 people, a local aid group said, one of the deadliest bouts of violence in the country in recent years.

The fighting in West Darfur province comes as Sudan has been plunged into turmoil since a military coup last year. The takeover upended the country's transition to democracy after a popular uprising forced the removal of longtime autocrat Omar al-Bashir in April 2019.

The clashes raise questions over whether military leaders are capable of bringing security to Darfur, which has been wracked by years of civil war. In 2020, the U.N. Security Council ended its peacekeeping mission there.

Adam Regal, spokesman for the General Coordination for Refugees and Displaced in Darfur, said Sunday's fighting in West Darfur's Kreinik area also wounded 98 people.

The fighting grew out of the killing of two people by unknown assailants Thursday, he said.

Early Sunday, large numbers of people armed with heavy weapons launched a major attack on Kreinik, torching and looting properties, Regal said. The fighting lasted for several hours and forced thousands of people to flee their homes, he said.

Regal, whose group provides food and other assistance to displaced people in the region, shared footage of destroyed houses in the area, with some images showing pick-up trucks mounted with machine guns.

The clashes eventually reached Genena, where militias and armed groups attacked wounded people while they were being treated at the city's main hospital, said Salah Saleh, a doctor and former medical director at the hospital.

"The area was burned down, and many people were killed. ... There was no intervention" from the local government to stop the fighting, he said.

Authorities said they deployed more troops and a military aircraft to the region since fighting on Thursday left eight dead and at least 16 wounded.

Volker Perthes, the U.N. envoy for Sudan, deplored "the heinous killings of civilians ... as well as the attacks on health facilities" in West Darfur.

He called for an in-depth and transparent investigation and to hold those responsible accountable.

Darfur has seen bouts of deadly fighting between rival tribes in recent months as the country remains mired in a wider crisis following the October coup. Kreinik was the scene of clashes in December that killed at least 88 people.

The Security Council terminated the peace-keeping mission UNAMID on Dec. 31, 2020. Since then, sporadic intercommunal clashes have increased in the region.

In December, Human Rights Watch urged the U.N. to deploy monitors to Darfur, saying that the departure of UNAMID caused a "gap in monitoring the abuses" fueled by impunity for atrocities committed in in the region.

The yearslong Darfur conflict broke out when rebels from the territory's ethnic central and sub-Saharan African community launched an insurgency in 2003, complaining of oppression by the Arab-dominated government in the capital, Khartoum.

The government of al-Bashir responded with a campaign of aerial bombings and raids by the janjaweed militias, which have been accused of mass killings and rapes. Up to 300,000 people were killed and 2.7 million were driven from their homes in Darfur over the years.

Al-Bashir, who has been in prison in Khartoum since his ouster, is wanted by the International Criminal Court over charges of genocide and crimes against humanity related to the Darfur conflict.

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