FEAR is Wang Qishan’s favoured weapon. As leader of the Communist Party’s most sustained and wide-ranging anti-corruption campaign in its history, he often urges his investigators to be “frightening”. One story goes that at a meeting of the party’s Central Commission for Discipline Inspection (CCDI), convened after Mr Wang took charge of it in November 2012, senior members—themselves among the most feared officials in the party—were presented with dossiers of their own sins. Mr Wang’s aim, it appeared, was to terrorise the enforcers themselves. Failure to uncover high-level graft, he has warned them, would be “dereliction of duty”.

At the time, a few were said to have grumbled—relentlessly pursuing the powerful over ill-gotten gains had not been a common feature of the unruffled life of a CCDI official. Before taking up the job, corruption had not even been Mr Wang’s preoccupation. A one-time banker and mayor of Beijing, he had gained a reputation as a troubleshooter during crises such as a deadly outbreak of Severe Acute Respiratory Syndrome in 2003 and the global financial crisis of 2008-09. To foreign dignitaries he even came across as affable: the professorial face of a secretive leadership. Now few dare to complain. At the age of 66, Mr Wang is the sixth-ranking member of the Politburo but is clearly second only to President Xi Jinping in the power he wields. He is perhaps the most feared.

On Mr Xi’s behalf, Mr Wang (pictured, left, with Mr Xi) has waged an assault on the vast machinery of the party that is unprecedented in its scale, complexity and ambition. Its targets have included high-ranking opponents of Mr Xi, but it is more than just a vendetta. Fear has spread throughout the bureaucracy and the management of state-owned enterprises. Mr Wang’s army of hundreds of thousands of party investigators, who have licence to detain and interrogate suspects without legal restraints, have taken down senior officials in redoubts such as the domestic security apparatus and the People’s Liberation Army, powerful state-owned enterprises and state regulators.

More than one-third of provinces have lost at least one member of their senior party leadership to corruption inquiries. The coal-mining province of Shanxi has lost the majority of its 13-member party leadership. Last year Mr Wang authorised the punishment of nearly 200 of his own investigators there. The largest oil company, China National Petroleum Corporation, has lost so many senior executives that designated replacements are reportedly at the ready should more disappear into Mr Wang’s clutches. That is likely: those detained are pressed—and sometimes tortured—into confessing and giving up more names in a secretive, extralegal system known as shuanggui. Dozens of generals and numerous former aides to party elders, all the sorts of people usually spared such treatment in the past, have been caught in the dragnet. Long dreaded by party officials, the shuanggui system is said by some to have become even more brutal. Officials have said they “would rather see the devil” than Mr Wang.

Normal bureaucratic life has been widely disrupted. The party has acknowledged that many officials are so afraid that they try to avoid making important decisions for fear of standing out—who knows what secrets their rivals might divulge to investigators? Provinces and ministries gutted by the CCDI squads are in desperate need of personnel. On March 6th the party chief of Shanxi said his province still needed to fill nearly 300 vacancies left by graft investigations there, including the most senior party posts in three cities. Many officials will not be keen to apply, so tainted by corruption is Shanxi’s reputation.

Mr Wang and Mr Xi may deem such disruption to be an acceptable risk. From almost his first day in power Mr Xi has declared the party to be riddled with corruption; life-threateningly so, indeed. Predecessors have used similarly strong language, but Mr Xi appears to be taking the problem far more seriously. This partly relates to the scale of it: recent years of double-digit growth in a flimsy legal environment have enabled officials to make fabulous sums of money through graft. It also relates to a broader political concern, that corrupt networks have become an obstacle to the economic reforms needed to sustain growth in the years ahead. The party describes anti-graft investigators as breaking “factions” that have subverted central authority by blocking its reforms. Hence state-owned enterprises that control vital areas of the economy, including the energy sector, are among the main targets.

For now, Mr Xi and Mr Wang seem to have the support of those around them. The other five members of the party’s highest ruling body, the Politburo Standing Committee, endorsed the detention of Zhou Yongkang, a former chief of domestic security who himself served on the committee until he retired in 2012 (he is the first man of his rank to be charged with corruption in the party’s history). The same was true for Xu Caihou, a retired vice-chairman of the military high command, who was formally detained last year (he died of cancer on March 15th), and would be true for his fellow retired vice-chairman, Guo Boxiong, whose detention appears likely. By targeting such figures (Mr Xu and Mr Guo were the armed forces’ two most senior officers) Mr Xi has strengthened his grip on the security establishment. Investigators appear to be preparing political charges against Mr Zhou, possibly that he colluded with a former Politburo member, Bo Xilai (now serving a life sentence), as well as with generals; many suspect they tried to challenge Mr Xi’s rise to power.

Mr Xi, Mr Wang and others on the Politburo Standing Committee have paid visits to members of the so-called “red nobility”, as relatives of former leaders are often described, to secure their co-operation. (Mr Xi and Mr Wang are princelings themselves.) Families belonging to the party aristocracy have so far escaped the worst of the anti-corruption campaign, but they have been told to turn over illegal assets to the state and rein in extravagant spending. Those so instructed have included Mr Xi’s own relatives, who were reported by Bloomberg in 2012 to have amassed hundreds of millions of dollars (though the news service found no indication of wrongdoing by them or Mr Xi). It also includes associates of Jiang Zemin, a former president and party chief.

It is certain that some in the elite are resentful, though the threat they may pose to Mr Xi is hard to calculate. The inner debates of China’s leadership are cloaked in intense secrecy. Last autumn sources close to the party leadership said they expected the anti-corruption campaign to wind down soon because of bad morale in the bureaucracy. That may have been wishful thinking: if anything, the campaign is intensifying. In the seven months to March 20th, 24 more ministerial-level officials have been detained for corruption, bringing the total to 69 in 28 months—more than double the number than in the previous five years under Mr Xi’s predecessor, Hu Jintao. More than twice as many senior officials were investigated by prosecutors for corruption last year than in 2013 (see chart).