In phone interview with AP news agency, a defiant TPLF leader calls on Abiy Ahmed to withdraw troops from the region.
Relief agencies in Ethiopia prepared convoys on Thursday to truck aid into the Tigray region, where a month of war is feared to have killed thousands of people and has forced refugees to flee along corpse-strewn roads.
Prime Minister Abiy Ahmed declared victory over the Tigray People’s Liberation Front (TPLF) after federal forces captured the northern region’s capital Mekelle at the weekend.
However, TPLF leaders have dug into surrounding mountains in an emerging guerrilla strategy.
“The war is a people’s war and will not end easily,” TPLF spokesman Gebre Gebretsadkan said on Tigray TV, adding that fighting had continued around Mekelle.
One aid worker in touch with Tigray told Reuters news agency that clashes had been taking place to the north, south and west of the city.
The government did not immediately respond to a request for comment.
Diplomats in touch with sources on all sides say thousands of combatants and civilians appear to have died since Abiy’s offensive began on November 4, after a TPLF attack on a military base was the last straw in their feud.
More than 45,000 refugees have crossed into neighbouring Sudan, while many more have been displaced within Tigray.
One refugee, who gave his name only as Abraham, saw corpses in civilian clothes as he fled the Tigrayan town of Humera towards the border with Sudan.
“Nobody can bury them, they were outside on the road,” he told Reuters from Hamdayet, a Sudanese border transit point.
Ethiopia’s government and the TPLF have both accused each other of targeting civilians – and both denied it.
The TPLF said it had destroyed government tanks and accused Eritrea of deploying troops to back Abiy. Eritrea’s government could not be reached for comment, but has previously denied that.
Claims from all sides have been hard to verify while access to the Tigray region has been blocked and communications largely down, though internet and phone services were returning this week.
Al Jazeera’s Mohamed Vall, speaking from the Hashaba refugee camp in Sudan near the border with Ethiopia, said hundreds of refugees there had lost contact with their loved ones.
“They don’t know the whereabouts of their mothers, fathers, sisters. That is the most traumatic aspect of what is going on in these camps,” he said.
In a breakthrough, the United Nations said on Wednesday that the UN and the Ethiopian government had signed a deal to allow “unimpeded” humanitarian access, at least for areas under federal government control, allowing food, medicines and other aid into the region of six million people.
Food stocks are nearly empty for 96,000 Eritrean refugees in Tigray, aid agencies say, while medics in Mekelle are short of painkillers, gloves and body bags.
“Aid is needed now as there’s an acute shortage of food, medicine and other relief,” tweeted Norwegian Refugee Council head Jan Egeland, saying relief convoys were ready to go.
The first video from Mekelle since its capture on Saturday, released by state-run ETV on Wednesday, showed people shopping and sitting on stools, as well as the Ethiopian military moving on the main streets.
One resident said shops and businesses are starting to reopen a month after hostilities broke out.
“As you can see, people are returning to their activities. The city has returned to its peacefulness,” said Mekelle resident Atikilt Kiros in footage that could not be independently verified.
“Businesses are beginning to open up. And as you may have noticed, we are going to church.”