Two suspected members of an Ethiopian regional militia plotting an attack died on Friday along with a civilian during a shootout with police, the authorities said in the capital.

The Fano self-defence militia took up arms against government forces they had formerly supported in the Ahmara region a year ago.

In February, parliament extended a state of emergency imposed last August in Amhara -- the country's second most populous region with 23 million people -- in an attempt to quell a Fano insurgency which until today had not reached Addis Ababa.

The Fanos and other Amharas felt betrayed by a peace agreement signed in November 2022 by the government and Tigrayan rebels -- long-time foes of Amhara nationalists who claim parts of Ethiopia's northernmost region as their ancestral lands.

Three members of the "extremist Fano group ... who were operating in Addis Ababa with a mission to commit (a) terror attack have been uncovered through the monitoring done by security bodies," a police statement said.

"During the operation ... to apprehend the terrorists ... the extremists were asked to surrender themselves... however they were unwilling and opened fire on police officers," from a car close to Bole international airport, it added.

One of the three was shot dead, a second died of his wounds in hospital while the third was arrested, the statement said.

Two policemen were wounded in the exchange.

The suspects killed a civilian who "refused to collaborate/assist" when they took over his vehicle, police said.

Human rights groups have denounced increased repression of divergent views in Ethiopia, a mosaic of more than 80 ethno-linguistic communities and 120 million people.

On April 4, Human Rights Watch called for the United Nations to investigate "war crimes" allegedly committed by the Ethiopian army in Amhara.

The Ethiopian Human Rights Commission, a public independent institution, has estimated that at least 45 people were killed on January 29 by government forces in Merawi city after clashes with the Fano militia.