A new bout of violence in Sudan’s war-torn Darfur region has left more than 60 people dead, the United Nations said Sunday. The clashes threaten to derail a fragile transition to democracy more than a year after the military’s ouster of longtime autocrat Omar al-Bashir.

The U.N. Office for the Coordination of Humanitarian Affairs in Sudan said about 500 armed men on Saturday attacked the village of Masteri, located 48 kilometers (30 miles) south of Genena, the provincial capital of West Darfur province.

The clashes between the Masalit and other Arab tribes in the area started earlier Saturday and lasted until late Sunday, state-run SUNA news agency reported, citing unnamed sources. Local authorities asked for military reinforcements to halt the clashes, the report said.

The SUNA report did not provide a death toll, but said dozens of people were killed or wounded, and more than 60 wounded were taken by helicopter to Genena for treatment.

An unconfirmed number of houses were looted and burned in the village, along with half the local market, OCHA said. The village borders Chad.

The attack prompted around 500 people to start a protest camp in front of the Masalit Sultan House, a settlement hosting about 4,200 internally displaced persons in Masteri, the U.N. agency said. The protesters called for authorities to protect them from attacks.

Saturday’s attack was the latest in a series of attacks in the area. OCHA documented at least seven from July 19-26 which left dozens dead or wounded.

Last week, local authorities in West Darfur declared a 24-hour curfew in Genena, compromising access to nutrition, water and sanitation, education, health and other critical services, OCHA said.

The clashes have come in the middle of the agricultural season, increasing humanitarian needs in the region. About 2.8 million people in the Darfur region are estimated to be severely food insecure from June to September, more than 545,000 of them in West Darfur alone, OCHA said.