Fighting has ravaged swathes of the country since last year's putsch, which sparked renewed clashes with ethnic rebels and the formation of dozens of groups now battling the junta.
Myanmar junta troops are committing war crimes by laying landmines on a "massive scale" around villages where they are battling anti-coup fighters, rights campaign group Amnesty International has said.
Fighting has ravaged swathes of the country since last year's putsch, which sparked renewed clashes with ethnic rebel groups and the formation of dozens of "People's Defence Forces" now battling the junta.
During a visit to Kayah state near the Thai border, Amnesty researchers interviewed landmine survivors, medical workers who had treated them and others involved in clearing operations, the organisation said on Wednesday.
It said it had "credible information" that the military had used mines in at least 20 villages, including on paths to rice fields, resulting in civilian deaths and injuries.
Amnesty also said it had documented several instances where the military had laid mines around a church and on its grounds.
"Soldiers have placed landmines in people's yards, at the entrance of homes, and outside toilets," Amnesty said. "In at least one documented case, soldiers booby-trapped a house stairwell with a trip-wire improvised explosive device."
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Anti-junta group members were attempting to de-mine some areas, but the work was done "by hand with only rudimentary equipment and without any professional training," it added.
"We know from bitter experience that civilian deaths and injuries will mount over time, and the widespread contamination is already blocking people from returning to their homes and farmland," said Rawya Rageh, the group's senior crisis adviser.
Myanmar is not a signatory to the United Nations convention that prohibits the use, stockpiling or development of anti-personnel mines. Its military has been repeatedly accused of atrocities and war crimes during decades of internal conflict.
Following the coup that ousted Aung San Suu Kyi's government, the military has waged a bloody crackdown on dissent that a local monitoring group says has killed more than 2,000 people and seen almost 15,000 arrested.
Scattered pro-democracy rallies were held across Myanmar on Tuesday to mark the 75th anniversary of the assassination of the independence hero General Aung San, father of Suu Kyi.
The protests generally dispersed within a short time to avoid confrontations with security forces.
The opposition National Unity Government, which was established by elected lawmakers and considers itself the country’s legitimate administration, broadcast a livestream of the commemoration ceremony on social media.
Mahn Winn Khaing Thann, the shadow prime minister of the government that the ruling military considers a terrorist organisation, promised to fight until freedom is restored in Myanmar.
“I would like to reiterate that the entire population, including monks, students, and youth, can only exercise their freedom of choice and fully enjoy their rights after ending the military dictatorship” and restoring democracy, he said.
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