Forces in Ethiopia's northern Tigray region have fired rockets at airports in a neighbouring state, in a widening of their conflict with the government.
Tension between the government and the Tigray People's Liberation Front (TPLF), which controls Tigray, boiled over into military clashes this month.
Officials said "airport areas" had been damaged in the rocket attacks. The TPLF confirmed responsibility, saying the strikes were retaliatory.
It comes after reports of a massacre.
Human rights group Amnesty International said it had confirmed that "scores, and likely hundreds, of people were stabbed or hacked to death" in the town of Mai-Kadra (May Cadera) on 9 November.
Prime Minister Abiy Ahmed has accused forces loyal to Tigray's leaders of carrying out the mass killings, while the TPLF has denied involvement.
Mr Abiy ordered a military operation against the TPLF earlier this month after he accused them of attacking a military camp hosting federal troops - claims the TPLF deny. There have since been a number of clashes and air strikes in the region.
The deadly fighting in Tigray has forced thousands of civilians to cross the border into Sudan, which says it will shelter them in a refugee camp.
Getting independently verified information about the situation in Tigray is hard because phone lines and internet services are down.
What do we know about the rocket attack?
The Ethiopian government's emergency task-force said rockets were fired towards the cities of Bahir Dar and Gondar, in Amhara state, late on Friday.
"The TPLF junta is utilising the last of the weaponry within its arsenals," it wrote in a statement, adding that an investigation had been launched.
An official told Reuters news agency that one rocket hit the airport in Gondar and partially damaged it, while a second one fired simultaneously landed just outside of the airport in Bahir Dar.
Details on casualties were not immediately clear.