Girma Gelam, Oromia region's police deputy commissioner, told media that 156 people have died in the riots, including 11 members of security forces, Xinhua news agency reported.
Police in Addis Ababa said Tuesday that 10 people were killed in the riots, including two police officers.
Hachalu Hundessa, a singer who focused on the rights of the country's Oromo ethnic group and became a popular voice in a wave of protests that led to the downfall of the previous prime minister in 2018, was shot dead by unidentified gunmen on Monday.
Following his death, huge protests erupted in Addis Ababa and Oromia region, the homeland of the Oromo people.
According to media reports, the authorities have shut down the internet in parts of country to curb the spread of the protests.
About 2,200 people were arrested on suspicion of involvement in the riots, government sources said, adding that the protests and riots had been under control as of Saturday.