Reports say China's sacked Railway Minister is under investigation for allegedly taking more than 122 million dollars in kickbacks linked to rail construction projects. The global times newspaper said Liu Zhijun, who was sacked last month, allegedly took payouts for doling out contracts for the rapid expansion of China's booming high-speed railway system, amounting to up to four per cent of each deal. It said, since Liu became rail minister in 2003, China's spending on high-speed rail construction has skyrocketed, with investment surpassing 700 billion yuan last year. Liu is the highest-ranking official to be placed under investigation since former Shanghai Communist Party head Chen Liangyu was dismissed in 2006 and later convicted of corruption in a case that highlighted China's graft problem.