Security forces in the city of Monywa opened fire on anti-coup protesters on Saturday, killing at least two people according to local media.
Thai authorities along the country's northwestern border braced themselves Monday for a possible influx of more ethnic Karen villagers fleeing new airstrikes from the Myanmar military.
The prisoners appear to be the hundreds of students detained in early March while demonstrating against the February 1 coup that ousted the elected government of Aung San Suu Kyi.
At least 15 people have died and hundreds are injured and missing after a devastating fire destroyed thousands of shelters in a sprawling Rohingya refugee camp in southern Bangladesh, a UNHCR spokeswoman said.
In Myanmar's hinterland, army uproots ethnic Karen villagers
"We will never give up to an unjust military but we will carve our future together with our united power," Mahn Win Khaing Than, who was named the acting vice president by Myanmar's ousted lawmakers, said on Saturday.
Aung San Suu Kyi was arrested during the February 1 coup. This is the fifth offence she has been charged with since then.
The demonstrators used water, blankets and fire extinguishers to try to smother the smoking canisters but were eventually forced to give ground and disperse.
The incident happened shortly after riot police attacked a large, peaceful protest against the military junta in Mandalay.
The escalation of violence in Myanmar as authorities crack down on protests against the February 1 coup is raising pressure for more sanctions against the junta.
Security forces in Myanmar escalated their crackdown on protests against last month’s military coup, with at least 38 people killed on Wednesday.