Demonstrators flooded the Ethiopian capital Addis Ababa on Monday, blocking roads and shutting businesses in an explosion of anger following the killing of 23 people on the city’s outskirts over the weekend.

The unrest in Ethiopia’s largest city was the latest instance of ethnic violence to challenge Prime Minister Abiy Ahmed, who has undertaken aggressive reforms including reigning in the security forces since his April inauguration.

Police appeared spread thin as groups of mostly young men waving protest flags and tree branches jogged through neighbourhoods across the city to denounce the weekend killings in the Burayu suburb.

Ethiopia’s police chief, Zeynu Jemal, said officers had shot dead five people on Monday, describing them as “dangerous vagrants” who attempted to loot property and steal police weapons.

State-owned Ethiopia News Agency (ENA) said the violence in Burayu was carried out by an organised mob, who looted, killed and forced 886 people out of their homes, citing Alemayehu Ejigu, police commissioner for the Oromia region that surrounds Addis Ababa and includes Burayu. Local media reported up to 200 arrests.