A series of deadly airstrikes by Myanmar’s military on a civilian crowd has sparked widespread condemnation, as witnesses recounted the horror of the attack that could be the junta’s deadliest since a coup two years ago. The initial death toll stood at 53 from Tuesday’s attacks on a village ceremony in Sagaing region at which women and children were present, but later tallies reported by independent media raised it to about 100. Myanmar’s air force dropped multiple bombs while attack helicopters strafed the civilian gathering of several hundred people, said Duwa Lashi La, acting president of the National Unity Government (NUG), which was set up to oppose junta rule. The US called on the regime to stop the “horrific violence”. The state department spokesperson Vedant Patel said: “These violent attacks further underscore the regime’s disregard for human life and its responsibility for the dire political and humanitarian crisis in Burma following the February 2021 coup.” Nabila Massrali, a spokesperson for EU foreign affairs and security policy, said: “The EU is deeply shocked by reports of the latest atrocity committed by the military regime in Sagaing, taking the lives of dozens of innocent civilians. We will continue to work to hold those responsible fully accountable.” Germany’s foreign office said it “strongly [condemns] the Myanmar army’s airstrike killing dozens of civilians, including many children,” adding: “We expect the regime to end the violence against its people immediately.” UN rights chief Volker Türk said he was “horrified” by the airstrikes whose victims he said included schoolchildren performing dances, with the global body calling for those responsible to be brought to justice. Tom Andrews, a UN special rapporteur on human rights in Myanmar, criticised the international response to the crisis in Myanmar: “The Myanmar military’s attacks against innocent people, including today’s airstrike in Sagaing, is enabled by world indifference and those supplying them with weapons. How many Myanmar children need to die before world leaders take strong, coordinated action to stop this carnage?” Aung Myo Min, minister of human rights at the NUG, said: “Only last week, the UN’s HRC [human rights council] passed a resolution that condemned the junta’s deliberate use of force against civilians and called on the junta to immediately cease all airstrikes. The junta has answered in the only way it knows how – through intensified atrocities and bloodshed.” Images shared online that appeared to have been taken after the attacks on the village of Pa Zi Gyi showed people in civilian clothes dead on the ground beside a destroyed structure. In a video, a man can be heard saying: “If you have survived, please make a sound.” He tells others: “If you hear a shout, help them. Go, go.” Sagaing region – near the country’s second-largest city, Mandalay – has put up some of the fiercest resistance to the military’s rule, with intense fighting raging there for months. Kyaw Wunna, a rescue worker, told the Guardian on Wednesday that he and four friends with three motorbikes had been on their way to attend a ceremony at the new administration building that had been completed only a week ago. “We were only a few minutes away there. We even heard the Dhamma song coming from the ceremony. Then we heard a very loud noise. So we threw our bikes into the drain on the side of the road and hid in there,” he said. “Afterwards, we heard the sounds of shootings from the sky for about 15 minutes,” he added: “rat-a-tat-tat”, followed by the roaring sounds of rockets. Once the jets left, they rushed to the ceremony site. “It was all tattered and torn. Everyone was dead,” he said. “Yet it was hard to tell who was who. We had to guess by looking at the faces. Some [we] were even not sure if they were men or women, because their body parts were all scattered in pieces and burnt,” he added. In videos of the devastated village seen by AP, survivors and onlookers stumble through the area of the attack amid clouds of thick smoke, with only the skeleton frame of one building still standing in the distance. The videos could not immediately be verified but matched other descriptions of the scene. The military took responsibility for the airstrike but denied it had killed civilians, claiming instead it had targeted “terrorists”. In response to accusations of abuses, the military government often accuses pro-democracy forces of terrorism. “Yes, we launched the airstrike,” military spokesperson Zaw Min Tun told a state-backed television channel, adding that the buildings nearby had exploded because anti-junta forces known as the People’s Defence Forces – the armed wing of the NUG – had stored ammunition there. “That’s why it exploded and people died,” he said. On social media, many turned their profile pictures black in tribute to those killed, while Duwa Lashi La asked neighbouring countries to provide humanitarian assistance to Sagaing and other regions engulfed in the conflict. Montse Ferrer, an Amnesty International business and human rights researcher, said there was an urgent need to suspend the supply of aviation fuel to Myanmar’s military. “This supply chain fuels violations of international humanitarian law, including war crimes, and it must be disrupted in order to save lives,” Ferrer said. “Unlawful air attacks killing and injuring civilians and destroying homes are a trademark of the Myanmar military, which goes to despicable lengths to crush resistance and instil fear in the population. Myanmar’s civilians bear the brunt of these sickening tactics.” António Guterres, the UN secretary general, “strongly condemns the attack by the Myanmar Armed Forces today”, according to a statement by his spokesperson Stéphane Dujarric. Guterres “reiterates his call for the military to end the campaign of violence against the Myanmar population throughout the country”, Dujarric added.