Government forces close in on Tigray’s capital and renewed accusations of Eritrean involvement.

Explosions have rung out in Addis Ababa as fighting between Ethiopia’s federal forces and a coalition of armed opposition groups widens in the country’s north.

Three diplomatic sources told the Reuters news agency on Thursday that the blasts were heard overnight in the Ethiopian capital. The blasts came hours after Addis Ababa instituted a ban on drone-flying in the capital and surrounding areas.

A source linked to Ethiopian Peoples’ Forces Alliance for Survival told the agency the alliance had carried out several drone strikes in Addis Ababa, including some targeting the military’s headquarters.

The alliance unites seven armed groups, including the Tigray People’s Liberation Front (TPLF) and groups from the Amhara, Afar, Somali and Benishangul-Gumuz regions. It says it wants to remove Prime Minister Abiy Ahmed’s government.

Alliance fighters have also clashed with government forces in the neighbouring Afar region, where the authorities have renewed accusations of an Eritrean incursion.

Reporting from Afar on Wednesday, Al Jazeera’s Muhammed Taha Tawakel said fighting had moved from the Amhara region deep into Tigray as government forces advanced north, reaching within about 40 kilometres (25 miles) of Mekelle, its regional capital.

The TPLF, meanwhile, had pulled its fighters back to new positions, and some of its leaders had moved out of Mekelle, Tawakel said.

They were joined by thousands of civilians who fled the city fearing clashes, he said. Electricity and internet services in the region had been cut.

Last week, Tigrayan forces mounted a large offensive, which the TPLF calls a “defensive war” against federal drone and artillery strikes. Government troops and allied fighters have since launched a counteroffensive.

The federal government has accused neighbouring states of backing the coalition, which they deny.

The Afar front

In Afar, government forces told Reuters they have recaptured the towns of Erebti and Abaala, near the border with Tigray. The claim remains unconfirmed.

On Wednesday, Tawakel reported that the fight to control the towns was ongoing, and escalation in the northern region threatened to drag Ethiopia and Eritrea into a wider war.

He said mediation efforts by locals to persuade forces controlling Abala and Erebti to withdraw failed, and the state of more than 80,000 Afar residents trapped in the area is uncertain.

Tawakel said the fighting in Afar carries the risk of regional repercussions, potentially bringing Eritrea and Ethiopia into a wider war and poses a risk to food security if routes between Ethiopia and Djibouti are disrupted.

Fighting had also reached areas along Ethiopia’s borders with Eritrea and Sudan, he said, increasing the risk of regionalising the conflict.

Ahmed Hussein, Afar’s deputy governor, told Al Jazeera on Wednesday that Ethiopia had come under an unprecedented attack which he said sought to undermine the regional administration and install figures loyal to Eritrea.

He called on Asmara to withdraw from Afar territory and held it responsible for the safety of civilians in areas controlled by opposition groups.