The clashes occurred on the border between the central Oromia and western Benishangul-Gumuz regions.
Violence began when officials from Benishangul-Gumuz were killed by unidentified gunmen, said the Walta Media and Communication Corporate, citing the region's communications chief Zelalem Jaleta.
The clashes between youths from rival ethnic groups armed with rocks and knives forced tens of thousands of people to flee their homes with security forces deployed to pacify the area.
Benishangul-Gumuz is one of Ethiopia's nine regional states, stretching to the border with Sudan.
The UN humanitarian office OCHA said some 70,000 people had been displaced in the wave of violence. In its latest update, OCHA said the fighting began last Wednesday with the death of the four high-ranking officials.
While Ethiopia's new Prime Minister Abiy Ahmed has received praise from around the globe for his reformist agenda, a wave of communal violence -- mostly over land issues -- has marred the first few months of his rule.
At least 58 people were killed in September when fighting broke out in the capital, with those fleeing saying they were targeted by Oromo mobs because they are members of minority ethnic groups.
Fighting between the Oromo -- the country's largest ethnic group -- and the Gedeo minority in the south of the country meanwhile has displaced nearly one million people.
