Ethiopian refugees, who fled the fighting in Tigray region, gather at a border reception center in Gedaref, eastern Sudan, on Nov 29, 2020. (ASHRAF SHAZLY / AFP)

ADDIS ABABA/NAIROBI - The leader of rebel forces in northern Ethiopia said on Monday they were still fighting near the regional capital of Mekelle, which fell to government troops at the weekend after nearly a month of battles and air strikes.

Debretsion Gebremichael, who heads the Tigray People's Liberation Front (TPLF), denied reports that he had fled to South Sudan and said he was still resisting in Tigray

"I'm close to Mekelle in Tigray fighting the invaders," Debretsion Gebremichael told Reuters in a text message, which the government dismissed as a deluded claim.

The war in Tigray region has killed hundreds and probably thousands, sent refugees into Sudan, enmeshed Eritrea, impeded a peacekeeping mission in Somalia, and heightened frictions between Ethiopia's myriad ethnic groups.

Prime Minister Abiy Ahmed's government launched an offensive on Nov 4 against the Tigray People's Liberation Front (TPLF), accusing the ex-guerrilla movement, which dominated national government for nearly three decades until 2018, of insurrection.

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TPLF leader Debretsion, a 57-year-old former radio operator, denied reports that he had fled to South Sudan and said his forces had captured some soldiers from neighboring Eritrea around Wukro, about 50 kilometers north of Mekelle.

Abiy's spokeswoman Billene Seyoum dismissed Debretsion's comments, saying: "The Federal government as a priority is busy governing a country and bringing stability to those affected.

Tracking and responding to the many delusions of a disintegrating criminal clique that has become irrelevant is not our focus."

Guerrilla war feared

There was no immediate comment from the Eritrean government, though at the start of the conflict it had denied involvement.

The TPLF has shelled Eritrea's capital Asmara.

Claims from all sides are difficult to verify since phone and internet links to Tigray have largely been down and access has been tightly controlled since the war began.

Ethiopian PM Abiy Ahmed told parliament on Monday that his troops had not killed a single civilian and were protecting Mekelle from damage

When he took office in 2018, Abiy pledged to unite Ethiopia's 115 million people, but there have been repeated bouts of bloody ethnic violence and hundreds of thousands have had to flee their homes.

Both sides have spoken of hundreds of dead in the Tigray war, and diplomats believe the toll is in the thousands.

READ MORE: Foreign powers press Ethiopia for peace talks over Tigray

Debretsion's defiant comments raise the spectre of a drawn-out guerrilla war. The battle-hardened TPLF helped to topple Ethiopia's Marxist dictatorship in 1991 and knows how to exploit its mountainous terrain and borders with Sudan and Eritrea.

Abiy won a Nobel Peace Prize last year for making peace with Eritrea, whose government also regards the TPLF as an enemy.

The US State Department reported six explosions in Asmara on Saturday night, but without specifying the cause. Diplomats told Reuters they had been either rockets or missiles.

Ethiopia is a major contributor to an African Union peacekeeping force fighting al Qaeda-linked militants in Somalia, but has disarmed several hundred soldiers there of Tigrayan ethnicity, questioning their loyalty.

The war in Tigray region has killed hundreds and probably thousands, sent refugees into Sudan, enmeshed Eritrea, impacted a peacekeeping mission in Somalia, and heightened frictions between Ethiopia's myriad ethnic groups.

In a text message to Reuters, Debretsion Gebremichael, who heads the Tigray People's Liberation Front (TPLF), denied reports that he had fled to South Sudan and said he was still resisting in Tigray.

"I'm close to Mekelle in Tigray fighting the invaders," he said. Debretsion added that his soldiers had captured some Eritreans fighting alongside the Ethiopian federal forces.

Billene Seyoum, the spokeswoman for the Prime Minister Abiy Ahmed, told Reuters that Debretsion should be ignored.

"The Federal government as a priority is busy governing a country and bringing stability to those affected. Tracking and responding to the many delusions of a disintegrating criminal clique that has become irrelevant is not our focus," she told Reuters.

There was no immediate comment from the Eritrean government, though at the start of the conflict it had denied involvement.

The TPLF has fired rocket at Eritrea's capital Asmara.

Claims from all sides are difficult to verify since phone and internet links to Tigray region have been largely down and access tightly controlled since the war began on Nov 4.