Geneva, (tate Observer):UN chief Antonio Guterres on Monday condemned the "brutal force" used by those behind Myanmar's coup and urged the military to immediately halt the repression and release prisoners. In his annual address to the UN Human Rights Council, Guterres mentioned only one country by name: Myanmar. "Today, I call on the Myanmar military to stop the repression immediately," he said, speaking in a pre-recorded video message at the opening of the Geneva-based council's 46th session. "Release the prisoners. End the violence. Respect human rights, and the will of the people expressed in recent elections," he said, insisting that "coups have no place in our modern world." Myanmar's authorities have gradually ratcheted up their tactics against a massive and largely peaceful civil disobedience campaign demanding the return of ousted civilian leader Aung San Suu Kyi. Saturday marked the deadliest day since the February 1 coup, with two people killed after security forces fired on a rally in Mandalay and a third man shot dead in Yangon. And the junta warned protesters against inciting people "to a confrontation path where they will suffer the loss of life." Protesters on Monday were undeterred by the warning, with tens of thousands rallying in Yangon, Myanmar's biggest city and commercial hub. Guterres had already condemned Saturday's "deadly violence", insisting in a tweet Sunday that "the use of lethal force, intimidation and harassment against peaceful demonstrators is unacceptable." Myanmar's foreign ministry hit back, accusing the UN and a number of foreign countries of "flagrant interference" in its internal affairs. The United States, Britain and Canada have all responded to the coup with sanctions targeting Myanmar's top generals. Even before the coup, army chief General Min Aung Hlaing -- who now holds legislative, executive and judicial powers -- was facing sanctions for his military's role in a brutal crackdown on the Rohingya Muslims in 2017. European Union foreign ministers will meet Monday to discuss their own measures against the regime.