An official from the party of deposed Myanmar leader Aung San Suu Kyi died overnight in police custody, associates said, while protests were held in at least half a dozen cities in some of the most widespread action against the coup last month.
The cause of Khin Maung Latt's death was not known, but Reuters saw a photograph of his body with a bloodstained cloth around the head. Sithu Maung, a member of the dissolved parliament, said in a Facebook post that Khin Maung Latt was his campaign manager and was arrested on Saturday night in the Pabedan district of Yangon.
Police declined to comment.
Security forces cracked down on many of the protests across the country on Sunday.
Police fired tear gas and stun grenades in the direction of protesters in Yangon and in the town of Lashio in the northern Shan region, videos showed.
A witness said police opened fire to break up a protest in the historic temple town of Bagan, and several residents said in social media posts that live bullets were used.
There was no word of any casualties.
Video posted by media group Myanmar Now showed soldiers beating up men in Yangon, where at least three protests were held despite overnight raids by security forces on campaign leaders and opposition activists.
The United Nations says security forces have killed more than 50 people to stamp out daily demonstrations and strikes in the Southeast Asian nation since the military overthrew and detained Suu Kyi on Feb. 1.
"They are killing people just like killing birds and chickens," one protest leader said to the crowd in Dawei, a town
in Myanmar's south. "What will we do if we don't revolt against them? We must revolt."
Yangon residents said soldiers and police moved into several districts overnight, firing shots.
They arrested at least three people in Kyauktada Township, residents there said. They did not know the reason for the arrests. "They are asking to take out my father and brother. Is no one going to help us? Don't you even touch my father and brother. Take us too if you want to take them," one woman screamed as two of them, an actor and his son, were led off.
Reuters was unable to reach police for comment. A junta spokesman did not answer calls requesting comment.
The state-run Global New Light Of Myanmar newspaper quoted a police statement as saying security forces were dealing with the protests in accordance with law. It said the forces were using tear gas and stun grenades to break up rioting and protests that were blocking public roads.
"PUNCHED AND KICKED"
Well over 1,700 people had been detained under the military junta by Saturday, according to figures from the Assistance Association for Political Prisoners advocacy group. It did not give a figure for overnight detentions.
"Detainees were punched and kicked with military boots, beaten with police batons and then dragged into police
vehicles," AAPP said in a statement. "Security forces entered residential areas and tried to arrest further protesters, and shot at the homes, destroying many."
The killings have drawn anger in the West and been condemned by most democracies in Asia. The United States and some other Western countries have imposed limited sanctions on the junta.
China, Myanmar's giant neighbour to the northeast, said on Sunday it is prepared to engage with "all parties" to ease the crisis and is not taking sides.
"China is...willing to contact and communicate with all parties on the basis of respecting Myanmar's sovereignty and the will of the people, so as to play a constructive role in easing tensions," State Councillor Wang Yi, China's top diplomat, told a news conference.
Protesters demand the release of Suu Kyi and respect for November's election - which her party won in a landslide but which the army rejected. The army has said it will hold democratic elections at an unspecified date.
Israeli-Canadian lobbyist Ari Ben-Menashe, hired by Myanmar's junta, told Reuters the generals are keen to leave politics and seek to improve relations with the United States and distance themselves from China.
He said Suu Kyi had grown too close to China for the generals' liking.
Ben-Menashe said he had also been tasked with seeking Arab support for a plan to repatriate Muslim Rohingya refugees, hundreds of thousands of whom were driven from Myanmar in 2017 in an army crackdown after rebel attacks.