The attack, shortly before 3pm local time, comes as the junta battles widespread armed opposition to its 2021 coup and its soldiers accused of bloody rampages and using air and artillery strikes to punish civilian communities.

"They were civilians who came to drink tea and sitting at the shop," Lway Yay Oo, a spokesperson for the Ta'ang National Liberation Army (TNLA) said.

At least four civilians were wounded and were receiving treatment in a hospital, she said.

Local media reported that 11 people had died and that many were injured in an army air attack on Lansan tea shop.

Since last year the military has lost swaths of territory near the border with China in northern Shan state to an alliance of armed ethnic minority groups and "People's Defence Forces" battling to overturn its coup.

The groups have seized a regional military command and taken control of lucrative border trade crossings, prompting rare public criticism by military supporters of the junta's top leadership.

Myanmar has been in turmoil since the military deposed Aung San Suu Kyi's government in 2021 and launched a crackdown that sparked an armed uprising.