Clashes between police and protesters erupted on Thursday when people blocked the main road in Ambo, some 130 kilometers west of the capital Addis Ababa.
One resident said the killings occurred around midday Thursday in the town of Ambo. Another resident said gunshots could be heard since morning.
Earlier reports said five people had been killed after security forces fired on angry protesters.
“They (police) then fired live rounds. We know of ... five people who died from gunshot wounds,” said a protester at the scene of the clashes. Another demonstrator said he saw at least 10 people transferred to hospital over gunshot wounds.
Addisu Arega Kitessa, a spokesman for the regional government, confirmed casualties in Oromiya.
“Demonstrations happening in Ambo have resulted in death and injuries,” said the official in a Facebook statement, adding that the protests were organized by “enemies” of the region.
Violence in Oromiya began in 2015 when people became angry over government plans to implement a development scheme for Addis Ababa. Opponents called the plan a land grab. A parliament-mandated investigation said some 700 people were killed in the first bout of violence that year.
The government imposed a state of emergency last year after protests became broader with a focus on politics and human rights abuses. The nine-month emergency law was lifted in August.
Hundreds of thousands of people have also been displaced along Oromiya’s border with the country’s Somali region in the violence that erupted last month. A total of 11 people were also killed in the region this week as a result of ethnic clashes.
Ethiopia has managed to spur high economic growth in the country over the past years but it faces mounting criticism over lack of political freedoms. Authorities deny they are deliberately curbing freedom of speech and say rebel groups and dissidents abroad are to blame for stirring violence.