In Yangon, riot police and soldiers hunted down protesters beginning in the morning, killing at least four people.
Several wounded people were hauled away by fellow protesters, leaving bloody smears on pavements, media images showed.
She made the remarks when Myanmar security forces killed at least 18 protesters and injured over 30 others around the country on Sunday in the bloodiest day since the February 1 coup, according to the U.N. Human Rights Office.
According to an Assistance Association for Political Prisoners report on Tuesday, more than 30 people have been killed and 1,200 arrested for opposing the coup since the military seized power.
Police also hurled stun grenades outside a Yangon medical school, sending doctors and students in white lab coats scattering.
Despite using live bullets, stun grenades and tear gas, police failed to disperse demonstrators taking part in a nationwide general strike against the military regime on Sunday. According to AAPP, the number of those arrested, charged, or sentenced rose to total of 1,132 people on Sunday.
According to OHCHR, police and military confronted peaceful demonstrators using disproportionate force with deaths reported in the largest city Yangon, Dawei, Mandalay, Myiek, Bago and Pokokku.
The victims have been identified as Myo Naing Lin, who suffered a gunshot wound to the chest, and Kyel Sin, who was shot in the side of her head, emergency workers and family members told Myanmar Now.
After comments by the Special Envoy of the UN Secretary General to Myanmar, Christine Schraner Burgener, Myanmar's Permanent Representative to the United Nations in New York, Ambassador Kyaw Moe Tun, gave a powerful intervention in which he denounced the military's seizure of power, confirmed that the country's legitimate authority is represented by the elected parliamentarians who constitute the Committee Representing the Pyidaungsu Hluttaw, and called on UN member states "to use any means necessary to take action against the Myanmar military".
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They suggested people pay tribute to him by donating to his foundation or to charities who would plant trees in his name . Ms Teixeira added: "Daddy, I am so proud of you, what you achieved your whole life and especially in the previous year ".
Three men were killed and at least 20 others injured when security forces moved on a rally in the southern coastal hub of Dawei. The army said a policeman had been killed.
Defiance of the coup has emerged not just on the streets but more broadly in the civil service, municipal administration, the judiciary, the education and health sectors and the media. We are deeply concerned over the loss of innocent lives and injuries during the ongoing situation in Myanmar. "Targeting of civilians is abhorrent", the US embassy said.
The Canadian Embassy said it was appalled.
Worldwide concern about the turmoil mounting but the Association of Southeast Asian Nations (ASEAN) failed to make a breakthrough in a virtual foreign ministers' meeting on Myanmar on Tuesday. The group said that while it had documented 75 new arrests, it understood that hundreds of other people were also picked up Saturday in Yangon and elsewhere. Many of those detained were taken to Insein Prison in Yangon's northern outskirts, historically notorious for holding political prisoners. "How does that make things better?" he said.
"What we really need is a coordinated effort by the global community to have targeted sanctions against the senior generals involved in this coup... and on military owned businesses", she said. "We can't accept that".
Tom Andrews, a United Nations special rapporteur, said it was clear the junta's assault would continue so the worldwide community should ratchet up its response.
Some of Myanmar's regional neighbours have condemned the coup, with Singapore's premier Lee Hsien Loong this week saying the country's return to military rule was "an enormous tragic step".
Suu Kyi was detained in Naypyidaw, the nation's capital, before dawn on the day of the coup, and had not been since in public since.
Ms Suu Kyi was detained and slapped with several charges including possessing illegal walkie-talkies and violating the country's Natural Disaster Law by breathing COVID-19 protocols.
The veteran human rights lawyer said the hearing would focus on case management and the timeline for the trial.