Explosions were heard overnight in Ethiopia’s capital Addis Ababa, three diplomatic sources said on Thursday, adding to anxiety about the possible spread of renewed conflict in the country’s north. A source linked to the opposition alliance fighting government forces since last week said it had carried out several drone strikes in Addis Ababa, including some targeting the military’s headquarters. Federal troops and allied militiamen, meanwhile, made fresh gains in the northern Tigray and Afar regions in fighting with the opposition Tigray People’s Liberation Front (TPLF), a pro-government militia said. Reuters could not independently verify the different claims. The diplomatic sources, who gave scant details of the blasts in Addis Ababa, spoke on condition of anonymity to discuss a sensitive matter. Witnesses said ‌there was no ‌damage visible near the military base. If confirmed, it would be the first known ‌drone attack by anti-government forces on the Ethiopian capital, which is hundreds of kilometres from the front lines in the northern regions of Tigray, Amhara and Afar. Spokespeople for Prime Minister Abiy Ahmed’s office, the federal government, the Ethiopian National Defence Force (ENDF) and the TPLF did not respond to requests for comment. Last week’s clashes were the biggest escalation in Ethiopia since the end of a 2020-2022 civil war that killed hundreds of thousands. The national intelligence service has banned drones over Addis Ababa. Opposition forces had not previously been known to use armed drones but there is growing evidence they may possess some capability. On Tuesday, the pro-government Tigray Peace Forces (TPF) militia ‌said it had captured drone frames and batteries from forces linked ‌to the TPLF, which is the main political party in Tigray. Edward Bach, Senior Africa Analyst at risk intelligence company Verisk Maplecroft, ‌said the opposition’s ability to strike Addis Ababa would be “a political game-changer,” undermining any government narrative that ‌the capital is unaffected by the war and narrowing a key tactical advantage for federal forces, their aerial superiority. The TPLF has formed an alliance with six other armed groups aiming to overthrow Abiy’s government. Federal forces have been advancing in southern Tigray, edging closer to the regional capital Mekelle, while the opposition alliance has captured towns in ‌neighbouring Afar. The pro-government TPF said on Thursday that it had captured the Tigrayan town of Maychew alongside the ENDF. Maychew is about 75 km (47 miles) south of Mekelle, surrounded by mountainous terrain that could be used for an assault on the regional capital. Federal forces captured Mekelle within the first month of the last war as TPLF fighters withdrew into the surrounding mountains. The TPLF then mounted a counter-offensive that reclaimed Mekelle seven months later. Pro-government forces also recaptured the town of Erbeti in Afar, which TPLF forces had seized at the start of the conflict, the TPF said on X, thanking the ENDF for “magnificent air support”. In Afar, where the TPLF captured several towns in the early days of the new conflict, fighting has forced tens of thousands of people to flee their homes, Valerie Browning, a founder of the Afar Pastoralist Development Association, told Reuters. Ethiopia’s government has accused Sudan, Egypt and Eritrea — which fought in support of Ethiopia’s federal government in the last war — of supporting the opposition alliance. All three deny that. Afar’s chief administrator Haji Awol Arba went a step further earlier this week, telling Al Jazeera that Eritrean soldiers had crossed into Afar to join the alliance’s offensive. Eritrea’s information minister did not immediately respond to a request for comment.