The severe drought in East Africa has led to fighting over water resources between Somali tribes in Ethiopia.
People are walking up to 70km in search of water
At least 12 people have died and over 20 have been wounded in clashes in Yamarug village on the Somali border.
Fighting broke out on Wednesday after the drought in the region increased competition for water and pasture.
The clashes were between members of the Marehan and Majereteen factions of the Darod clan. Parts of Somalia are in the grip of the worst dought in 40 years.
"The fighting has not stopped and miltiamen from both sides heading to reinforce the area," an unnamed local official told the AFP news agency.
The Ethiopian government is sending a fact-finding mission to the area, an Information Ministry official told AFP.
Observers say there had been long-standing tensions between the two factions in the area, but they had lived alongside each other peacefully before the drought made water resources scarce.
In southern Somalia, people are starting to die from thirst as a result of the drought, aid agency Oxfam said this week.
The World Meterological Association has warned the Horn of Africa will remain in the grip of a drought until at least April.
The United Nations estimates more than 11m people in parts of Kenya, Ethiopia, Somalia, Eritrea, Tanzania and Burundi need food aid for the next six months.