The death toll from a Myanmar military air raid in northern Kachin state has risen to 80, according to reports, as human rights groups accused the ruling generals of violating the laws of war and called on the international community to impose a ban on the sale of arms and aviation fuel to the country.

The number of casualties from the bombing of hundreds of people who had gathered to celebrate the founding of the Kachin Independence Organisation on Sunday night appeared to be the single-worst air attack since Myanmar’s military seized power in February 2021.

As many as 80 people were killed, and about 100 were injured, a spokesperson for the Kachin Artists Association told The Associated Press news agency by phone on Monday. Initial reports had counted 60 dead, but sources close to Kachin Independence Army officials said about 80 people were now known to have died, the spokesperson said.

He said military aircraft dropped four bombs on the celebration on Sunday evening, which was attended by between 300 and 500 people, including musicians and other performers.

Those killed also included Kachin military officers and soldiers, musicians, jade mining business owners, other civilians, and cooks working backstage, he added.

A Kachin singer and keyboard player were among the dead, said the spokesperson, who asked not to be identified because he feared punishment by the authorities.

It was not possible to independently confirm details of the air raid in the far north of the country, though media sympathetic to the Kachin posted videos showing what was said to be the devastating attack’s aftermath, showing splintered and flattened wooden structures.

The Kachin News Group also reported that government security forces had blocked the wounded from being treated at hospitals in nearby towns.

Amnesty International called on the military to grant medics and humanitarian organisations access to the area and to those affected by the air attacks.

“We fear this attack is part of a pattern of unlawful aerial attacks by the military which has killed and injured civilians in areas controlled by armed groups,” Amnesty’s deputy regional director, Hana Young, said in a statement.

“The military has shown ruthless disregard for civilian lives in its escalating campaign against opponents. It is difficult to believe the military did not know of a significant civilian presence at the site of this attack,” she said.

‘Necessary operation’
The Myanmar military government’s information office confirmed in a statement late on Monday that there was an attack on what it described as the headquarters of the Kachin Independence Army’s 9th Brigade, calling it a “necessary operation” in response to “terrorist” acts carried out by the Kachin group.

The military’s statement also called reports of a high death toll “rumours” and denied the military had bombed a concert and that singers and audience members were among the dead.

The United Nations office in Myanmar said in a statement earlier on Monday that it was “deeply concerned and saddened” by reports of the air raids.

Western embassies in Myanmar, including the United States, issued a joint statement saying the attack underscores the military regime’s “disregard for its obligation to protect civilians and respect the principles and rules of international humanitarian law”.

The reports of the deadly attack come just days ahead of a special meeting of the foreign ministers of the Association of Southeast Asian Nations (ASEAN) to discuss the widening violence in Myanmar.

Myanmar has been beset for decades by conflicts related to the independence struggles of ethnic minorities, but anti-government resistance has increased markedly nationwide since the military’s coup in 2021 and the formation of an armed pro-democracy movement opposed to military rule.

The Kachin Independence Army is one of the stronger ethnic rebel groups and is capable of manufacturing some of their own armaments.

Sunday’s celebration was held to mark the 62nd anniversary of the founding of the Kachin Independence Organisation. It included a concert and was held at a base also used for military training near Aung Bar Lay village in Hpakant township, a remote mountainous area 950km (590 miles) north of Myanmar’s biggest city, Yangon.

Human Rights Watch (HRW) called the raids an “apparent violation of the laws of war, which prohibit attacks causing indiscriminate or disproportionate civilian harm”, and called for more punitive measures against Myanmar’s military.

“This horrific attack should trigger renewed efforts by concerned states to enforce tougher sanctions on the junta, including cutting off its access to foreign currency revenues as well as arms and aviation fuel”, HRW’s Asia Director Elaine Peterson said. 

Eight local Myanmar groups also backed the call for renewed sanctions, calling the attack “inhuman”.

“These deliberate bombing attacks on a large civilian gathering which have resulted to mass killing is a serious commission of war crime”, the groups that included All Kachin Students’ Federation and Women’s League of Burma said in a statement.