Hanoi, Vietnam — Vietnamese authorities arrested a pro-democracy activist, state media said, the latest in a crackdown on political dissidents in the southeast Asian country. Tran Khac Duc, 29, was held on charges of “creating, storing, distributing or disseminating information, documents and items aimed at opposing the Socialist Republic of Vietnam,” according to the publication Safeguarding the Law. He was arrested in September, but authorities only announced his detention through state media on Saturday. Duc is affiliated with the Assembly for Democracy and Pluralism organization, whose website says it aims to “establish a multi-party democratic system” in the communist nation.