Clashes over pasture between farmers and herders in Sudan's western region of Darfur killed three civilians on Sunday, a doctors' committee linked to the country's protest movement said.
"Three citizens were killed this morning in Shengel Tobay, in North Darfur state, and another was wounded," the Central Committee of Sudan Doctors said.
Violence over grazing land, which was one of the root causes of a deadly war that erupted in 2003, has been relatively rare in Darfur recently.
The latest incident marred the first day of the Eid Al Adha and was Sudan's first since months of protests brought down longtime ruler Omar Al Bashir and created an opportunity for civilian rule.
Ethnic African rebels took up arms against Mr Al Bashir's regime, which they accused of marginalising the remote region, in the war that broke out more than 15 years ago.
Khartoum armed Arab pastoralists to quash the rebellion, leading to massacres that resulted in genocide charges against Mr Al Bashir and others in international courts.
While the fighting has subsided in Darfur, tension over pasture remains and those responsible for the war's darkest hours have not been brought to justice.
"The former regime fuelled the conflict and contributed to deepening the crisis by not helping to provide sustainable solutions, and not holding perpetrators accountable," the doctors committee said.
Mr Al Bashir was removed in April after 29 years in power and a temporary power-sharing agreement was reached a week ago by the country's generals and civilian protest leaders.
But the document that will serve as Sudan's de facto interim constitution does not mention the fate of Mr Al Bashir and others wanted by the International Criminal Court.