Citing residents in the Sagaing region, BBC Burmese, Radio Free Asia (RFA), and the Irrawaddy news portal reported between 100 and 150 people, including civilians, had died in the attack.
Reuters could not immediately verify the reports and a spokesperson for the ruling military did not answer a phone call seeking comment.
Myanmar has been in turmoil since a 2021 coup, with attacks by ethnic minority armies and resistance fighters challenging the rule of the military, which has responded with air strikes and heavy weapons, including in civilian areas.
A member of the local People’s Defense Force (PDF), an anti-junta militia, said fighter jets had fired on a ceremony held to open their local office.
“So far, the exact number of casualties is still unknown. We cannot retrieve all the bodies yet,” said the PDF member, who declined to be identified.
At least 1.2 million people have been displaced by post-coup fighting, according to the United Nations.
Tuesday’s incident could be one of the deadliest among a string of air strikes since a jet attacked a concert in October, killing at least 50 civilians, local singers and members of an armed ethnic minority group in Kachin State.
Myanmar’s pro-democracy government-in-exile, the National Unity Government, condemned the attack, calling it “yet another example of (the military’s) indiscriminate use of extreme force against civilians.”
Last month, at least eight civilians including children were killed in an air strike on a village in northwest Myanmar, according to a human rights group, ethnic minority rebels and media.
The military has denied international allegations it has committed atrocities against civilians and says it is fighting “terrorists” determined to destabilize the country.
Western countries have imposed sanctions on the junta and its vast business network to try to choke off its revenue and access to arms from key suppliers like Russia.Myanmar’s military has launched air attacks on a central town known to be a bastion of opposition to the coup carried out two years ago.
Witnesses and local media said dozens of people were killed and wounded in the attack on Tuesday – one of the worst since the military seized control of the country.
Citing residents in the Sagaing area – about 110km (45 miles) west of the main city Yangon – news reports said at least 30 people, including civilians, had died in the barrage on the town of Pazigyi.
The air raids occurred as residents gathered for the inauguration of an administrative office, Al Jazeera’s Tony Cheng reported, from Thailand’s capital Bangkok.
“At 7:35am the crowd was attacked by jets and those were followed by Mi-35 helicopters,” said Cheng, citing one rescuer at the scene.
“He confirmed 40 dead but he suspects the death toll will rise considerably – the carnage there was terrible. All the reports we’re seeing is that these were civilians, and far from being a legitimate military target.”
No immediate response from Myanmar’s military rulers was available.
Myanmar’s military has been accused of indiscriminate killings of civilians as it engages in major offensives to suppress armed resistance to its takeover.
Last month, Myanmar’s coup leader Min Aung Hlaing pledged to deal decisively with “terrorists” fighting against his rule.
On February 1, 2021, the military toppled the elected government of Aung San Suu Kyi, prompting peaceful protests that security forces suppressed with bloody violence that escalated since then and has been been characterised by United Nations experts and others as a civil war.
More than one million people have been displaced as the military steps up artillery attacks and air raids.
A military spokesperson told Al Jazeera recently that previously reported attacks blamed on its forces have been “misreported”.
Western countries have rolled out sanctions against the ruling generals in a bid to choke off revenue and access to military equipment from key allies and suppliers such as Russia.
