"Night time drone attack in Mekele. No conceivable military targets!" Tigray People's Liberation Front (TPLF) spokesman Getachew Reda said on Twitter.

"Mekele Hospital among the targets and at least three bombs dropped," he added.

Kibrom Gebreselassie, chief clinical director at Mekele's Ayder Referral Hospital, also said on Twitter there had been a drone attack "close to midnight" near Mekele general hospital.

"Casualties are arriving to Ayder Hospital," he said.

Another senior Ayder hospital official, Hayelom Kebede, said in a brief message to AFP that two injured people had been taken to the facility so far.

The attack was reported just days after at least four people including children were killed in another air strike on Mekele, with Tigrayan rebels accusing the government of hitting a residential area and a kindergarten.

Ethiopian government officials were not immediately contactable for comment on the latest reports.

Fighting erupted between government forces and the TPLF in northern Ethiopia last Wednesday, ending a five-month truce and dimming hopes for a peaceful resolution to the near 22-month war.