People carry an Ethiopian national flag in the streets after a national call to stand in honour of the Ethiopian National Defence Forces, in Addis Ababa, on November 17, 2020. (EDUARDO SOTERAS / AFP)

ADDIS ABABA - Ethiopia predicted swift victory but defiant northern rebels promised them "hell" on Wednesday in a two-week war threatening the vast country's unity and further destabilizing the Horn of Africa.

The war has killed hundreds, sent 30,000 refugees into Sudan, and called into question whether Africa's youngest leader, who won a Nobel Peace Prize in 2019, can hold together his nation's myriad fractious ethnic groups.

The war has killed hundreds, sent 30,000 refugees into Sudan, and called into question whether Africa's youngest leader, who won a Nobel Peace Prize in 2019, can hold together his nation's myriad fractious ethnic groups

Ignoring international appeals for talks, Prime Minister Abiy Ahmed's government says its forces are marching on Tigray's capital Mekelle and will soon triumph over the Tigray People's Liberation Front (TPLF), which he accuses of revolt.

The rebels say they have captured tanks and artillery in a string of victories despite being massively outnumbered.

"Tigray is now a hell to its enemies ... The people of Tigray will never kneel," they said in a statement.

The TPLF says Abiy, their ex-military comrade and one-time political partner, has removed Tigrayans from senior security and government posts since he took office in 2018 and now wants to dominate them completely.

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Abiy's government has put former officials - many Tigrayan - on trial for crimes like torture, murder and corruption, but denies any attempt at ethnic domination.

"The federal government... denounces, in the strongest of terms, mischaracterization that this operation has an ethnic or other bias," the government's task force on the crisis said.

Debretsion Gebremichael, elected Tigrayan president in polls that Ethiopia does not recognize, told Reuters by text that his forces had fallen back but denied government allegations they destroyed bridges and a road leading to the capital.

"We have shifted our defense line and as a result they get into some towns of South Tigray," he added.

The Tigrayan leaders accused federal forces of targeting civilians, churches and homes. The government says it is only targeting TPLF targets and has accused Tigrayan forces of using civilians as human shields.

CUT OFF

The northern state is largely cut off as media are barred, most communications are down and aid workers are pulling out, meaning Reuters could not verify assertions from either side.

Hundreds of thousands have been uprooted from homes, while internet, electricity and banking services have been blocked.

"Attempting to rule the people of Tigray by force is like walking on a burning flame," the Tigrayan statement added.

"Tigray will be the graveyard of dictators."

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Refugees have said militias from Amhara, the neighboring state, attacked them because of ethnicity and that airstrikes were killing civilians. However, Abiy's government has repeatedly denied an ethnic undertone, saying it is restoring law and order and guaranteeing national unity.

Aiby's parents are from the Oromo and Amharic ethnic groups - the largest and second largest respectively. Tigrayans represent about 5 percent of Africa's second most populous country. They dominated national leadership between 1991 and 2018, before Abiy took the premiership and began opening up both the economy and a repressive political system that had jailed tens of thousands of political prisoners.

In a rare comment on the activities of a past prize winner, the Nobel committee in Oslo expressed deep concern this week and urged peaceful resolution of the conflict.

'DEVASTATING HUMANITARIAN CRISIS'

The TPLF has also fired rockets into neighboring Eritrea, escalating the war beyond national borders. It has a long-standing enmity with President Isaias Afwerki's government. Abiy won his 2019 Nobel prize for a peace pact with Afwerki.

Ethiopia's army is one of Africa's best, but many senior officers were Tigrayan and much of its heavy weaponry was based in Tigray, which was on the front line of the two-decade standoff with Eritrea after a 1998-2000 war.

The Tigrayans are also a battle-hardened force with experience of fighting against Eritrea and spearheading the ouster of a Marxist dictatorship in 1991.

The International Committee of the Red Cross (ICRC) said healthcare facilities in Tigray and Amhara were short of supplies and assistance for many wounded.

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"We are seeing a devastating humanitarian crisis unfold, not just within Ethiopia but across its borders," said ICRC delegation head Katia Sorin.

"The telecommunications blackout in Tigray has made it practically impossible for people to contact their family members, causing fear and anguish."

One hospital in the city of Gondar in Amhara had treated more than 400 people injured in the conflict while also handling 14 COVID-19 patients, the ICRC said. Three Ethiopia Red Cross ambulances were attacked last week.

With ramifications of the conflict all over the region, Ethiopian peacekeepers helping curb Islamist militants in Somalia removed weapons from 200-300 of their Tigrayan soldier colleagues in the past week, the government and sources told Reuters.

That was due to concerns over their loyalty, and not their ethnicity, the government said.

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That was a headache for the Somalia operation, one security source said. "What do you do when you're a force commander and you find you have 200 or 300 soldiers who can't go into battle because of their ethnicity?" he asked.