•Much of northern Ethiopia is under a communications blackout and access for journalists is restricted, making battlefield claims difficult to verify independently.
•The UN estimates 100 trucks of food and non-food aid must reach Tigray each day but none have arrived since October 18.
A year ago, Prime Minister Abiy Ahmed deployed troops in Ethiopia's Tigray region, launching a campaign that he vowed would be swift and targeted.
Instead, it devolved into a prolonged war marked by atrocities and starvation, and fighting now threatens the Ethiopian capital.
How did we get here?
The 2019 Nobel Peace Prize winner said he aimed to detain and disarm leaders of the Tigray People's Liberation Front (TPLF), the regional ruling party which dominated national politics for three decades before Abiy took office.
The move was unavoidable, he said, after the TPLF staged attacks on army camps, but it also followed months of tensions between them.
After several weeks of air strikes and heavy fighting, federal forces took control of the regional capital Mekele and Abiy declared victory.
But the TPLF mounted a successful counterinsurgency.
By late June the rebels controlled most of the region again, prompting the military to largely withdraw and Abiy's government to declare what it described as a "humanitarian ceasefire."
Where is the fighting now?
The TPLF then launched offensives into the neighbouring Afar and Amhara regions.
Its leaders said their goals were to deny Abiy's forces the chance to regroup and re-enter Tigray and break what the UN describes as a de-facto aid blockade.
Abiy, in turn, called for mass mobilisation against the TPLF, which his government has officially designated a terrorist group.
Fighting has recently been concentrated in Amhara, south of Tigray, where the rebels have claimed control of two strategic towns on the highway to the Ethiopian capital.
An allied rebel group, the Oromo Liberation Army (OLA), also claims to have taken ground in the same area, roughly 325 kilometres (200 miles) north of Addis Ababa.
The government has denied rebel claims of gains but declared a nationwide state of emergency and ordered residents of Addis to prepare to defend their neighbourhoods.
Much of northern Ethiopia is under a communications blackout and access for journalists is restricted, making battlefield claims difficult to verify independently.
The TPLF has not ruled out a march on Addis Ababa, while a spokesman for the OLA told AFP on Wednesday the capital could be overrun within "months if not weeks."
Tigray itself has seen little fighting since late June, but the region has been pounded by air strikes in recent weeks.
What is the humanitarian situation?
More than 400,000 people in Tigray have "crossed the threshold into famine," the UN said in July, and conditions have deteriorated since then.
The UN estimates 100 trucks of food and non-food aid must reach Tigray each day but none have arrived since October 18.
Basic services including electricity, banking and telecoms "are being denied by the Ethiopian government", a US State Department spokesperson told AFP in September.
Earlier this month AFP documented starvation deaths in many parts of Tigray, citing internal documents from aid groups.
The government blames the TPLF for obstructing aid deliveries.
Hundreds of thousands of civilians have been displaced, while UN investigators say mass rape and other atrocities in Tigray could constitute crimes against humanity and war crimes.
What are the chances for peace?
The US on Wednesday said it would dispatch a special envoy, Jeffrey Feltman, for talks on Thursday and Friday to urge "dialogue" to resolve grievances, and in August the AU appointed Nigerian ex-president Olusegun Obasanjo as its regional trouble-shooter.
Abiy's government has framed the war as an internal "law enforcement operation" and resisted calls for mediation, which have become louder as fighting inches toward the capital.
The TPLF has not completely ruled out negotiations, but observers say the likelihood of talks are slim.
"I think, depressing as it is, more and more this does look to be playing out on the battlefield," said William Davison, senior Ethiopia analyst for the International Crisis Group (ICG).
"It would be delusional for anyone to think that things will go back to 'normal' after so much bloodshed and destruction," said Awet Weldemichael, a Horn of Africa security expert at Queen's University in Canada.