More than 400 people have been arrested in Ethiopia during investigations into ethnic and religious violence that left 78 people dead last week, a spokeswoman for Prime Minister Abiy Ahmed said Thursday.
Protests against Abiy erupted in Addis Ababa and in Ethiopia's Oromia region on October 23 after a high-profile activist accused security forces of trying to orchestrate an attack against him -- a claim police denied.
The unrest quickly devolved into ethnic and religious clashes that killed dozens of people over three days.
"The latest information that I have in terms of perpetrators that have been apprehended is 409 individuals," spokeswoman Billene Seyoum told a press conference.
She said investigations were ongoing and that more suspects could be taken into custody.
Billene said Thursday that the death toll had climbed to 78 -- up from the figure of 67 provided by a police official in Oromia last week.
Abiy, who came to power last year and was named this year's Nobel Peace Prize laureate, has been criticised for his government's response to the violence and specifically for waiting until the weekend to issue a statement.
Billene defended the response Thursday and dismissed descriptions of Abiy as "weak".
Ethnic violence has been a recurring problem under Abiy, causing Ethiopia to record more displaced people than any other country last year.
Billene said the violence is the work of unnamed "elements" that oppose Abiy's reform agenda, which has included freeing political prisoners and creating a more open political environment.
She also said the latest surge was partly a "backlash" against plans to transform Ethiopia's ruling coalition -- which has been in power for nearly three decades -- into a single political party.
The activist at the centre of last week's protests, Jawar Mohammed, is credited with helping to sweep Abiy to power last year but he has recently become critical of some of the premier's policies.
Both men are from the Oromo ethnic group, the country's largest, and their feud highlights divisions within Abiy's Oromo support base that could complicate his bid for a five-year term when Ethiopia votes in elections planned for May 2020.
Jawar, a media mogul, is highly divisive and accused by critics of fomenting ethnic divisions.
Abiy has faced pressure in recent days to take measures against Jawar, but Billene on Thursday declined to address whether the government held him responsible for the latest deaths.
"It's not about naming or not naming, but it's important for the due process of investigations to go through," she said.