Footages of a brutal crackdown on protests against a coup in Myanmar unleashed outrage and calls for a stronger international response Thursday, a day after 38 people were killed. Videos showed security forces shooting a person at point-blank range and chasing down and savagely beating demonstrators.

Despite the shocking violence the day before, protesters returned to the streets Thursday to denounce the military’s Feb. 1 takeover — and were met again with tear gas.

The international response to the coup has so far been fitful, but a flood of videos shared online showing security forces brutally targeting protesters and other civilians led to calls for more action. The United States called the images appalling, the United Nations human rights chief said it was time to “end the military’s stranglehold over democracy in Myanmar,” and the world body’s independent expert on human rights in the country urged the Security Council to watch the videos before meeting Friday to discuss the crisis.

The coup reversed years of slow progress toward democracy in Myanmar, which for five decades had languished under strict military rule that led to international isolation and sanctions. As the generals loosened their grip in recent years, the international community lifted most sanctions and poured in investment.

UN special envoy for Myanmar, Christine Schraner Burgener, described Wednesday as “the bloodiest day” since the takeover, when the military ousted the elected government of leader Aung San Suu Kyi. More than 50 civilians, mostly peaceful protesters, are confirmed to have been killed by police and soldiers since then, including the 38 she said died Wednesday.

”I saw today very disturbing video clips,” said Schraner Burgener, speaking to reporters at the UN in New York via video link from Switzerland. “One was police beating a volunteer medical crew. They were not armed. Another video clip showed a protester was taken away by police and they shot him from very near, maybe only one meter. He didn’t resist to his arrest, and it seems that he died on the street.”