Ethiopia’s army chief of staff and the regional president of the northern state of Amhara were killed in two related attacks when a general tried to seize control of Amhara in an attempted coup, the Prime Minister’s Office said on Sunday.

Amhara state president Ambachew Mekonnen and his adviser were shot dead and the state’s attorney-general was wounded in Amhara’s capital of Bahir Dar on Saturday evening, according to a statement from the office of Prime Minister Abiy Ahmed.

In a separate but related attack the same night, Ethiopia’s army Chief of Staff Seare Mekonnen and another retired general were shot dead in Seare’s home in Addis Ababa by his bodyguard.

Abiy’s office named Amhara state security head General Asamnew Tsige as responsible for the foiled coup, without giving details of his whereabouts. Asamnew was released from prison last year, having been given an amnesty for a similar coup attempt, according to media reports.

Abiy took office just over a year ago and embarked on unprecedented reforms in Ethiopia, Africa’s second-most populous country and one of its fastest-growing economies.

But the Premier’s shake-up of the military and intelligence services has earned him powerful enemies, while his government is struggling to contain growing ethnic violence, including in Amhara.

The shooting in Bahir Dar occurred when the state president — an ally of Abiy — was holding a meeting to decide how to rein in the open recruitment of ethnic militias by Asamnew, one Addis-based official told Reuters.

A week earlier, Asamnew had openly advised the Amhara people, Ethiopia’s second-largest ethnic group, to arm themselves in preparation for fighting against other groups, in a video spread on Facebook.

Bahir Dar residents said there was at least four hours of gunfire on Saturday evening and some roads had been closed off.

Abiy donned military fatigues to announce the attempted coup on state television on Saturday evening.

Early on Sunday, Brigadier General Tefera Mamo, the head of special forces in Amhara, told state television that “most of the people who attempted the coup have been arrested, although there are a few still at large”. He did not give details about Asamnew.

Since coming to power, Abiy has released political prisoners, removed bans on political parties and prosecuted officials accused of gross human rights abuses, but his government is battling ethnic bloodshed once held in check by the state’s iron grip.

Now some of Ethiopia’s myriad ethnic groups are disputing the boundaries of the country’s nine federal states, or arguing that they too should have regional governments, claims that threaten the dominance of other groups.

“He (Abiy) seems to be dismantling the EPRDF (ruling coalition) and is entertaining thoughts of altering the architecture of federalism, but he hasn’t given any clear direction he’s heading in,” said Matt Bryden, the head of regional think tank Sahan Research.

Abiy had also changed many senior security officials when he came to power, Bryden noted, creating more uncertainty that allowed armed groups that would once have been quashed to flourish. Seare was the third chief of staff Abiy had appointed.

Ethiopia is due to hold a national parliamentary election next year.