Scores of freshly-dug graves fill the church compound in Mai-Kadra. Shovels abandoned by weary hands are strewn on the dirt among empty cans of lemon air freshener that fail to mask the stench of death.

Elsewhere in this town in western Tigray, dozens of corpses still awaiting a grave lie abandoned in a roadside ditch, their exposed flesh rotting in the sun.

No-one denies that something terrible unfolded here: a massacre of hundreds of civilians, who were shot, slashed or stabbed with knives and machetes.

It is the worst-known episode of violence against civilians in the deepening bloodshed in northern Ethiopia.

But the dead are now pawns in a blame game. Participants in the three-week-old conflict are seeking to absolve themselves of an atrocity that bears the hallmarks of a war crime.

- Contested narrative -

The massacre on November 9 was revealed by rights group Amnesty International, using photo and video analysis and interviews with witnesses who said retreating forces loyal to the Tigray People's Liberation Front (TPLF) were responsible for killing ethnic Amhara residents of the town.

Prime Minister Abiy Ahmed's government has seized upon this narrative, the atrocity providing further arguments for pressing his offensive against the dissident leadership of the northern Tigray region.

On Tuesday, the Ethiopian Human Rights Commission (EHRC), a government-affiliated body, issued a report blaming a Tigrayan youth group as well as local police and militia for the massacre of at least 600 people it said were "pre-identified" by ethnicity.

But Tigrayan refugees who fled Mai-Kadra for Sudan instead say pro-government forces were responsible for the killings during a brutal assault on the town of 40,000 people.

- 'Ethnic cleansing' -

Last week AFP gained rare access to territory controlled by the federal government in the northern conflict zone and visited Mai-Kadra.

Amhara residents of the town said their Tigrayan neighbours had turned on them as the fighting drew close.

"Militiamen and police attacked us with guns, and civilians attacked us with machetes," said Misganaw Gebeyo, a 23-year-old Amhara farmhand now lying in a hospital bed, a ragged scar extending below the medical gauze encasing his head. "The whole population is involved."

He recalled hiding at home, watching in terror as assailants decapitated his friend with a machete. He too was hacked and left for dead.

"They wanted to exterminate the Amharas," Misganaw said.

The town's newly-appointed administrator, a government loyalist called Fentahun Bihohegn, described the massacre as an act of attempted "genocide" against his fellow Amharas.

"A brutal ethnic cleansing has been committed against the Amhara people," Fentahun said, describing the entire TPLF, whether leaders or members, as "criminals".

"For me, I have witnessed the real hell here in Mai-Kadra," he said.

- Corpses in the streets -

A different story of the massacre can be found a short distance to the west, in the mushrooming refugee camps across the border in Sudan.

"Ethiopian soldiers and Amhara militiamen entered the town and fired into the air and at residents," Marsem Gadi, a 29-year-old farmer who fled with thousands of other Tigrayans to the Um Raquba refugee camp, told AFP.

"We ran out of town to find safety. I saw men in civilian clothes attacking villagers with knives and axes," he said. "Corpses were lying in the streets."

When Marsem made it home later his house had been looted and his wife and three-year-old son were gone. "I don't know if they're still alive," he said. After that, he fled to Sudan.

Other refugees shared similar tales of attacks by pro-government forces, not TPLF.

Elifa Sagadi said she too ran for the safety of nearby fields when the gunfire started.

"On the road I saw at least 40 bodies. Some had bullets in their heads, others had been stabbed," she said of her return. "When I went home, my house was on fire and my husband and two sons had disappeared."

In a statement, the Ethiopian government seemed to dismiss all such testimony as the work of "TPLF operatives (who) have infiltrated refugees fleeing into Sudan to carry out missions of disinformation."

For his part, TPLF leader Debretsion Gebremichael rejected suggestions that his forces were responsible for the massacre as "baseless".

"It cannot be related to us. We have our values, we have our norms. We know how to handle people," he said.

Amnesty researcher Fisseha Tekle told AFP the stories heard in Mai-Kadra and Um Raquba could both be true: a tit-for-tat ethnic slaughter revealing the dangers of a conflict that could spiral out of control.

"We don't know the full extent of the situation," he said, adding the killings "may amount to war crimes".

- Deepening divisions -

The UN and human rights groups have called for an impartial investigation, but a communications blackout, restrictions on movement and continued fighting in Tigray make that unlikely in the short term.

Amharas and Tigrayans were uneasy neighbours before the current fighting, with tension over land sparking violent clashes.

That Mai-Kadra is now being run -- at least temporarily -- by Amharas provides relief to Amharas, even as it deepens Tigrayan fears of a takeover.

"Now I feel very free," said Adugna Abiru, an Amhara farmer who has worked in Mai-Kadra for two decades.

"Before, if you spoke on the phone in Amharic and not Tigrinya (the Tigrayan language), people would look at you. You didn't feel safe," he said.

Fentahun, the new administrator, who arrived after the federal government took control on November 10 and drives around in a pick-up truck with three armed guards, said he and his fellow Amharas did not want revenge against Tigrayans. He insisted there were still Tigrayan residents in Mai-Kadra, but was unable to identify any.

Nevertheless, he urged refugees to return home from Sudan -- something the federal government is also pushing even as the conflict escalates in the mountainous east where a siege of the regional capital is threatened.

"Our vision is to create a safe place for every Ethiopian," he said. "We want to make this a peaceful place where everyone can exist together."