Beijing police detained liberal writer Huang Zerong on charges of “provoking trouble” on Sunday after he reportedly criticised the Communist Party’s propaganda chief Liu Yunshan online. The 81-year old writer, better known by the alias Tie Liu, was taken from his home at around 1am, according to Huang’s wife. Police also took books, journals and a computer. Huang's wife has since been informed by police that her husband had been criminally detained on charges of “picking quarrels and provoking trouble”. A second person identified as Huang Jing was also detained. Chinese criminal procedure law restricts such detention periods to 30 days if suspects are not subsequently formally arrested and charged with a crime. Huang’s detention “makes him China’s oldest ‘picking quarrels and provoking trouble’ suspect,” Liu Xiaoyuan, a prominent lawyer and friend of Huang, wrote in a Tweet on Sunday evening. The detention for his critical writing comes almost six decades after Huang was first denounced as a “rightist” in Mao Zedong’s crackdown on liberals after the Hundred Flowers campaign, in which the party chairman briefly tolerated criticism but then purged those who spoke up. The then journalist in his twenties from Sichuan served 23 years in prison. The Communist Party cleared his name in 1980. In 2010, he vowed to set up a one million yuan fund to finance legal aid for writers and journalists. Radio Free Asia suggested Huang was detained for an article he wrote on the party’s propaganda chief. Huang has long been openly critical of Liu Yunshan, accusing him and his family of corruption in articles released online and calling on President Xi Jinping to dismiss the Politburo Standing Committee member.