At least 600 civilians were killed in a massacre in northern Ethiopia in early November due to their ethnicity, a state-appointed human rights watchdog has alleged. The Ethiopian Human Rights Commission (EHRC) on Tuesday released its preliminary report into the November 9 massacre at Mai-Kadra, a town in the Tigray region. The EHRC said a group of Tigrayan youths, called Samri, aided by local officials and police, "carried out door-to-door" raids, killing hundreds they identified as ethnic "Amharas and Wolkait". The commission accused the alleged perpetrators of committing "war crimes" before they retreated from the advance of the Ethiopian Defence Forces (EDF). People were beaten, stabbed, set on fire and strangled with ropes, the EHRC alleged. Many others were severely wounded and property was looted or destroyed, it added. The Tigray People's Liberation Front (TPLF) has previously denied its involvement in the attacks, but was not immediately available to comment on the report on Tuesday. Ethiopian Prime Minister Abiy Ahmed, <a href="https://www.thenationalnews.com/world/europe/ethiopia-s-abiy-ahmed-wins-nobel-peace-prize-2019-1.922113">last year's Nobel Peace Prize winner,</a> called the report findings "heart-wrenching" and urged the international community "to condemn these atrocious acts of crimes against humanity." The commission's findings couldn’t be independently verified but they mirror earlier accounts reported by Amnesty International, which cited witness statements, photos and videos as evidence. "The unimaginably atrocious crime committed against civilians for no reason other than their ethnicity is heartbreaking," EHRC chief Daniel Bekele said in a statement. "It is now an urgent priority that victims are provided redress and rehabilitation, and that perpetrators involved directly or indirectly at all levels are held to account before the law." Since fighting erupted in Ethiopia on November 4, hundreds have been killed and more than 41,000 refugees have fled to neighbouring Sudan amid the widespread destruction and uprooting of people from homes. The conflict has spread to Eritrea, with Tigrayan forces firing rockets at the city of Asmara. Mr Abiy on Sunday issued a 72-hour ultimatum to Tigray's forces, demanding they surrender, otherwise the army would be sent into the capital Mekelle on Wednesday. Heightening the rhetoric, <a href="https://www.thenationalnews.com/world/ethiopia-to-encircle-tigray-capital-with-tanks-and-artillery-says-military-1.1115592">the army said "there will be no mercy" for Mekelle's residents</a> when its soldiers "encircle" the city of about half a million people. But Tigrayan forces have vowed to keep fighting, and their leader Debretsion Gebremichael said they were "ready to die in defence of our right to administer our region". The United Nations on Tuesday expressed its concern about possible war crimes ahead of an army onslaught of Mekelle, amid reports of a heavy build-up of tanks and artillery around the city. Michelle Bachelet, UN High Commissioner for Human Rights, called on all sides to give "clear and unambiguous orders to their forces" to spare civilians. "The highly aggressive rhetoric on both sides regarding the fight for Mekelle is dangerously provocative and risks placing already vulnerable and frightened civilians in grave danger," Ms Bachelet said. "I fear such rhetoric will lead to further violations of international humanitarian law." The UN Security Council will hold its first meeting on Tuesday to discuss the conflict in Ethiopia's most northernly region. During his tenure as Prime Minister, Mr Abiy has been trying to distance the country’s politics from ethnic federalism that had been advantageous to the Tigrayan minority. By merging the ethnic and region-based parties of the Ethiopian People's Revolutionary Democratic Front, which had governed Ethiopia for 30 years, into a nationwide Prosperity Party, Mr Abiy threatened the power of the TPLF, which ethnically represents about 6 per cent of the population of Ethiopia. Tensions heightened when the TPLF refused to join the new party, and alleged that Mr Abiy was an illegitimate ruler. The Tigrayan party also held its own federal elections, in a repudiation of the prime minister's politics. The immediate cause of the conflict was an alleged attack on November 4 by Tigrayan forces on the headquarters of the Northern Command of the Ethiopian National Defence Force (ENDF), the military wing of the Ethiopian government.