ADDIS ABABA (Reuters) - Clashes over grazing and farm land killed 18 people last week near the southern Ethiopian town of Wondo-Genet, police said.

A police commander told Reuters the fighting on April 3 pitted members of the Gugi Oromo and Sidama clans, some 260 km (160 miles) south of the capital Addis Ababa.

"Clashes between the two clans have been brought under control and the government is investigating their cause," Demsash Hailu, public relations head of the Federal Police, said late on Tuesday.

Fighting between the two clans in the region, which is known for its hot springs and lush forests, flare up sporadically.

They normally centre on disputes over land used for grazing and for growing khat, a narcotic plant that is one of Ethiopia's main exports and chewed across east Africa and the Middle East.

(Reporting by Tsegaye Tadesse; Editing by Wangui Kanina)

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