China investigates ex-security chief

China's former security chief Zhou Yongkang is being investigated for suspected "serious disciplinary violation", state media say. The news confirms rumours about the hugely powerful former minister, who has not been seen in public for months. Mr Zhou headed China's Ministry of Public Security and was a member of the top decision-making body, the Politburo Standing Committee. The move to target him will send shockwaves through the political elite. With today's public disgrace of such a senior figure, Xi Jinping is signalling that his campaign is different”. He is the most senior Chinese official to be investigated since the Gang of Four - which included the wife of late leader Mao Zedong - in the early 1980s. Zhou Yongkang retired in late 2012, as Xi Jinping took over from Hu Jintao as the Communist Party leader and China's president, according to BBC.