Tar Parn La, a spokesperson and deputy general of Ta’ang National Liberation Army, one of three groups forming the Brotherhood Alliance, which led the operation, told the Guardian it had taken more than 100 military outposts.

China has called for stability on the border and has for months been signalling its desire for Myanmar to crack down on criminal scam operations targeting its nationals, which are booming in the area.

Myanmar’s military seized power in a coup in February 2021, and has since faced determined opposition from the public, including many who took up arms and formed people’s defence forces to overthrow its rule.

That the operation managed to progress so rapidly reflects the low morale and pressure on military resources, said Richard Horsey, Myanmar adviser to International Crisis Group, a non-profit that produces analysis of conflicts around the world.

A local resident of Lashio in northern Shan state told the Guardian that in the early hours of 27 October, as the offensive began, she could see missiles landing on military camps, in the mountains, about a 15-minute drive away.

Maung Saungkha, a prominent poet who joined the armed resistance after the coup, and whose group Bamar People Liberation Army, had coordinated with the Brotherhood Alliance, said last week’s operations had already prompted wider waves of attacks against the military across the country.

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