Gan Yisheng, secretary-general of the Communist Party's Central Commission for Discipline Inspection, said more officials may be implicated as the party probes deeper into the social security fund scandal that brought down Shanghai party boss Chen Liangyu, the South China Morning Post reported. Chen, whose sacking was announced on Monday, is the most senior official to be toppled by a corruption scandal in more than 10 years. Gan confirmed that more than US$500 million was misappropriated from Shanghai's social security fund, with most of the money invested in Shanghai. He refused to reveal other details of the case, including how Chen was involved, saying the investigation was still under way. Chen's sacking fuelled speculation that President Hu Jintao was seeking to consolidate his power by removing his political rivals ahead of a key party congress next year. Gan said the investigation into Chen was launched about two months ago and dismissed speculation the top leadership was divided over his removal.