At least 700 people have been arrested in a crackdown against the latest wave of violence to hit Ethiopia, official said.
The Federal Police Commissioner, Mr Zeynu Jemal, told reporters that the perpetrators of the violence involving two different political groups, had organised themselves under one command.
The robbers have worked deliberately to create tensions between the Oromos and the other communities living in the Oromia region, Mr Zeynu said.
Five people died in a street demonstration in Addis Ababa on Monday, while protesting against the killings and robberies in Burayu area on the outskirts of Addis Ababa.
The police said the protesters were killed when some tried to snatch rifles from the security agents trying to restore peace and order.
Police reports indicated that over 25 people were killed in weekend robbery incidents in Burayu. The late night robberies reportedly targeted members of the non-Oromo community, mainly the Gamo settlers in the Ashewa meda area.
The incidents have caused displacement of thousands of people who have sought refuge in Addis Ababa.
A mass rally
A police source said at least 23 people were killed in a weekend of violence in the ethnic Oromo heartland near the capital.
The unrest followed a mass rally last week marking the return home of the exiled Oromo Liberation Front (OLF) group leaders, which had fought an insurgency for self-determination for Oromos.
The incidents were the latest in a spate of attacks carried out along ethnic lines since reformist Prime Minister Abiy Ahmed came to power in April, the first Oromo leader in the ethnically diverse country’s modern history.