One of China's rising political stars, Zhou Yongkang, has returned to Beijing from a provincial posting and is expected to play a key role in overseeing the country's massive security machine, party sources said. Xinhua reported on Thursday that Mr Zhou was replaced by former minister of personnel Zhang Xuezhong as the party secretary of Sichuan province, but the report did not say what new job he would take. Mr Zhou's return to Beijing was widely expected. He was made a new member of the Communist Party's Politburo and a new member of the party central committee's secretariat at the party's 16th congress, which took place last month. Party sources said Mr Zhou, 60, would share responsibility for supervising and co-ordinating the mainland's security apparatus, including the police, armed police, courts and prosecution service. He is expected to report to Luo Gan, a new member of the Politburo standing committee - the party's highest decision-making body. Mr Zhou had also been rumoured to replace Jia Chunwang as minister of public security in March when the National People's Congress convenes to discuss and approve a massive government shake-up. However, sources said Mr Zhou now looked unlikely to take on that role as the government has favoured other candidates. They said Liu Jing, a deputy minister at the Ministry of Public Security, is one of the favoured candidates to take over Mr Jia's current position. Mr Zhou's new portfolio, if confirmed, would come as a surprise to some analysts as he has no political experience in the area of law and order. A graduate of the Beijing Petroleum Institute, Mr Zhou has worked for most of his career in the mainland's oil industry - mostly at the Liaohe Oilfield in the northeast of the country. In 1996, he became president of China National Petroleum Corporation, formerly the Ministry of Petroleum Industry. From 1998 to 1999 he was minister of land and resources. He was appointed party secretary of Sichuan in 1999. Mr Zhou will face a daunting task because the mainland's public order is under threat from a rising number of increasingly violent crimes. These stem largely from social discontent over soaring unemployment, corruption and widening income disparity. He is also expected to play a key role in the country's anti-terrorism efforts. Little is known about Zhang Xuezhong, the new man in Sichuan. He spent much of his career in the western province of Gansu. From 1990 to 1994 he was the deputy party secretary of Tibet, where he served under Vice-President Hu Jintao. The appointment of Mr Zhang will be seen as a step up for him, as Sichuan is playing a key role in Beijing's drive to develop the poorer western region.