On Monday, clashes were reported in the area around the town of Kobo, which lies in the Amhara region just south of Tigray and fell into the hands of rebel fighters at the weekend, prompting many residents to take flight.
"There is heavy fighting nearby. I was hearing the sounds of heavy weaponry starting from morning to around three pm," one Kobo resident told AFP on condition of anonymity after fleeing to Woldiya about 50 kilometres (30 miles) further south.
The resident said many people were flocking from nearby areas to the town, while ambulances were ferrying the wounded to medical facilities inside Woldiya or further afield.
"There is currently an air of uncertainty in Woldiya although it's slightly calmer than yesterday," the resident said, adding that the town was currently under a dusk-to-dawn curfew.
The government of Prime Minister Abiy Ahmed had announced Saturday that federal forces had pulled back from Kobo in order to avoid "mass casualties".
In turn, the Tigray People's Liberation Front (TPLF), which has been fighting government forces and their allies for almost 22 months, said it had captured a number of towns and cities in a counter-offensive.
The various claims could not be independently verified as access to northern Ethiopia is severely restricted.
A diplomatic source said there were clashes in an area about halfway between between Kobo and Woldiya on Monday, while a humanitarian source reported "heavy fighting" around the Zobel mountains southeast of Kobo.
On Friday, as conflict on the ground escalated, an air strike on Tigray's capital Mekele killed at least four people including two children, an official at the city's biggest hospital told AFP.
Tigrai TV, a local network, put the death toll at seven, including three children.
The international community has voiced deep alarm about the resumption of fighting in a conflict that has already caused the deaths of untold numbers of civilians and led to a desperate humanitarian crisis in northern Ethiopia.