A paper-cut made by an elementary school student from Jiangsu province shows the character "Lian", which means 'free from corruption'. SI WEI/CHINA DAILY

Gao Bo, deputy secretary of the China Anti-Corruption Research Center of the Chinese Academy of Social Sciences, said: "SOE directors should be made more aware of their responsibilities so they will raise standards and encourage clean governance. We also need to establish a permanent supervision mechanism to oversee the use of power and to punish corrupt officials."

President Xi told the January meeting of the CCDI that the complexity and intractability of corruption means China still faces tough challenges, and warned that the battle is far from over. Anti-corruption mechanisms have been put in place but they aren't perfect, so corruption still exists and temptations remain, he said.

According to Zhao Hongzhu, deputy head of the CCDI, some officials still abuse their power and accept huge bribes because they can quickly line their pockets with millions, or even hundreds of millions, of yuan.

Others use their powers to establish close political or economic interests with other officials and company directors. Many secretly form factions, he said. The central leadership is fully aware that, historically, corruption was at the heart of several dynastic collapses and the failures of established political parties.

The CCDI said it would attach great importance to investigating officials who continue to act corruptly or display low moral standards even in the face of the anti-graft campaign.

Other targets will include officials involved with political and economic cliques, and those with poor public reputations. The probity of officials likely to win promotion to key positions will also be investigated to ensure smooth progress.

"Efforts to rectify the four undesirable work styles - formalism, bureaucratism, hedonism and extravagance - should continue," President Xi said. "Our determination to use strong medicine to cure illness will not falter, and our strength to rid our bones of poison will not diminish," he added.

Sun Ruisheng contributed to this story.