Doctors in Bahir Dar, the capital of Ethiopia’s Amhara region, have told the BBC that a large number of civilians have been killed in recent fighting between local militias and government troops.
A doctor in the city’s main hospital said casualties included elderly people and a five-month old baby.
Residents said that a militia had taken control of a prison and released inmates.
Tensions have been rising since April when the government announced it was dismantling regional forces across Ethiopia, provoking protests by Amhara nationalists who said the move would weaken their region.
In a statement on Tuesday, the government said there was relative calm in parts of the region while measures were being taken to clear the two biggest cities, Bahir Dar and Gondar, of militias.
Ethiopian Airlines has announced it has suspended flights to four airports in the region – including Bahirdar and Gondar – for three days.