Associated Press journalist Thein Zaw remains detained after he was arrested Saturday morning by police in Yangon, Myanmar while covering protests against the military coup that unseated leader Aung San Suu Kyi’s elected government. According to the AP, he is being held in Yangon’s notorious Insein Prison, which has long been known for its inhumane treatment of political prisoners. “The Associated Press calls for the immediate release of AP journalist Thein Zaw, who was detained in Myanmar while doing his job,” said Ian Phillips, AP vice president for international news. “Independent journalists must be allowed to freely and safely report the news without fear of retribution. AP decries in the strongest terms the arbitrary detention of Thein Zaw.” Security forces in the capital city of Yangon opened fire on protesters Sunday, killing at least 18 and wounding 30, said the UN Human Rights Office, citing “credible information.”