The attack came on Thursday afternoon, a few miles outside the zonal capital Dangila city.
Hundreds of Abiy Ahmed's mercenary soldiers were travelling on several convoys from a small rural town called Addis Qidam to Dangala.
When they got to the outskirts, a squad of Fano fighters opened heavy fire with heavy weaponry and explosives which destroyed the convoys and set them ablaze killing hundreds.
Sources say the remaining mercenaries and Fano rebels continued fighting that lasted several hours into the night. Gojjam has been a stronghold for the rebels who are battling Abiy Ahmed's mercenary army since April 2023.
The war is in a stalemate over the last three months despite Abiy Ahmed's heavy aerial campaign. No breakthrough has been made by both forces.
Last week, Abiy Ahmed's mercenary army massacred hundreds of civilians in Merawi town, some 20 miles away from the regional Amhara capital, Bahir Dar. The massacre was confirmed by the US government and several other international groups.
Residents say it was committed as a retaliation by Abiy forces after an overnight attack on their base in the town that killed dozens of their fighters.
The Gojjam province has been a meatgrinder for Abiy Ahmed's mercenary army. Two powerful Fano groups are active in the province which hosts the Amhara capital, Bahir Dar. One faction called, the Gojjam command led by a young colonel named Zinabu has a strong presence in and around the regional capital. Another group called Amhara Popular Force controls large swaths of territory in east and west of the province and is led by Zemene Kassie.
Abiy Ahmed's mercenary army only uses arial transport to move in and out of the Amhara region. The neighboring Benishagul-Gumuz region is completely cut off by the rebels and there is no land transport even for civilians.
Abiy Ahmed, considered by many Ethiopians as an Oromo genocidal ruler, came to power in 2018 and ever since the country has been in a deadly civil war that has killed over a million Ethiopians.
Abiy Ahmed's ruling party, the Oromo Prosperity Party, is reportedly interested in restoring medial Oromo hegemony on the rest of Ethiopia at any cost with medieval means which led to barbaric war crimes in the northern region of Tigray and now Amhara.