"An official from ousted Myanmar leader Aung San Suu Kyi's party has died in custody following alleged torture, the second such death while in detention of junta forces this week, according to a watchdog group. The deaths have raised concerns about the condition and treatment detainees are receiving in detention. Since the military seized power in a coup on February 1, security forces quickly moved to stifle dissent and arrested government officials, protesters, journalists, civil servants and NGO workers, and repressed independent media. Many people have been taken arbitrarily in nighttime raids and their families do not know where their loved ones are, or what condition they are in, the United Nations said. Human Rights Watch said that people who are forcibly disappeared are more likely to be subjected to torture or ill-treatment than others arrested. The National League for Democracy's (NLD) Zaw Myat Lynn died in custody on Tuesday after he was arrested in the biggest city Yangon, Reuters reported, citing ousted parliamentarian Ba Myo Thein. Watchdog group Assistance Association for Political Prisoners (AAPP) released a statement saying "Zaw Myat Lynn, who was head of an educational institute, was announced dead today from injuries consistent with torture following an arbitrary nighttime raid." The exact cause of death is still unknown but AAPP added Zaw Myat Lynn was subjected to beatings. Shortly before his arrest, Zaw Myat Lynn posted a livestream on Facebook in which he said, "I want to encourage all citizens across the country that we will be protesting day and night for 24 hours against the dictatorship." He urged people to continue fighting the army, saying "we will risk our lives to defeat them." "We are showing to the international communities including UN and other agencies that we, citizens of Myanmar want democracy and we value democracy as the most precious thing in our lives," he said. It follows the death of a Yangon NLD party chairman Khin Maung Latt, who died while in custody on Saturday. "On the night of his arrest, Khin Maung Latt was tortured to death in his cell," AAPP said in a news release. Reports of bruising to Khin Maung Latt's head and body raised suspicions he had been abused, NLD lawmaker Ba Myo Thein told Reuters. CNN cannot independently verify this reporting and the details surrounding the deaths of Zaw Myat Lynn and Khin Maung Latt's are not immediately clear..."