The Chinese government continues to tighten its grip on social media by announcing on Wednesday two detentions and three additional cases under investigation, the Financial Times reported. Citizens have faced prosecution before for online posts, but this is the first announcement of cases by the central government. The State Internet Information Office, the central government regulator, detained a Shanghai man for posting a fake document pretending to be from the tax authority, and a student from Yunnan province was detained for spreading a rumor about the murder of eight village officials by a man dying from a pollution-related illness. The Central Committee of the Chinese Communist Party (CCP) pledged to punish those who spread “harmful information.” The announcement was accompanied by a lengthy document indicating the CCP intends to increase regulation, but not shut down, popular microblog sites such as Sina Weibo (SINA.NASDAQ). Sina has over 250 million users making 90 million posts each day.