"At least 38 people were killed after Myanmar's security forces opened fire on peaceful protesters in towns and cities across the country Wednesday, in scenes that have been described as "a war zone." Thousands of protesters across the Southeast Asian nation have taken to the streets over the past four weeks against a military coup on February 1. Security forces have intensified their response in recent days, opening live fire into crowds, and using tear gas, flash bangs and stun grenades on demonstrators. The United Nations said the total death toll since the coup was now 50, though activists put that total as higher. "Today was the bloodiest day since the coup happened," Special Envoy Christine Schraner Burgener told a briefing Wednesday. Around 1,200 people have been detained, while many relatives are unsure where they are being held, she said. "Every tool available is needed now to stop this situation," Burgener said. "We need a unity of the international community, so it's up to the member states to take the right measures." CNN reached out to the ruling military regime via email but has not yet received a response. Protesters run from police firing tear gas during a pro-democracy demonstration in Mandalay, Myanmar, on Wednesday. Protesters have for weeks been demanding the release of democratically elected officials, including the country's leader, Aung San Suu Kyi, who are currently in detention. Suu Kyi's National League for Democracy Party (NLD) won a landslide victory in November elections; military leaders allege voter fraud but have provided no proof for their claim. Burgener said that in discussions with the military, she had warned that the UN Security Council and members states were likely to take strong measures. "The answer was: 'We are used to sanctions, and we survived those sanctions in the past'," she said. "When I also warned they will go in an isolation, the answer was: 'We have to learn to walk with only few friends'." Security forces -- which include members of the military's Light Infantry Divisions long documented to be engaged in human rights abuses in conflict zones throughout the country -- escalated their deadly crackdown on peaceful demonstrators this week. "Today, the country is like the Tiananmen Square in most of its major cities," the Archbishop of Yangon, Cardinal Charles Maung Bo, said on Twitter. In one brutal instance, Myanmar security forces were caught on camera beating emergency services with the butts of their guns, batons and kicking them in the head, according to activist group Assistance Association for Political Prisoners (AAPP). The AAPP released the video on Wednesday and said in a statement that the leaked video was from North Okkalapa, in Yangon. The video provides a glimpse into the brutal methods deployed the security forces..."