BEIJING - As China's anti-graft campaign deepens, it seems that corrupt officials have also learnt some lessons from the fallen "tigers and flies," high-ranking officials and lowly bureaucrats.

A newspaper affiliated to the top anti-graft body on Saturday published a report detailing how corrupt officials tried to outwit graft-busters but still failed in the end.

The report cited 11 cases in which corrupt officials fabricated lies, agreed with others not to give away each other, colluded with others to devise a consistent story, transferred ill-gotten wealth and destroyed or made up evidence to stall investigation efforts.

Xu Gang, former deputy governor of southeast China's Fujian province, was found to have colluded with his wife and bribers and transferred the illicit money, it said.

Some powerful officials, it said, even took revenge on whistle-blowers.

"Corrupt officials' awareness and ability in counter-investigation have become more and more powerful, and they have shown a more frequent action to fight back," the report cited a local graft-buster in Jiangxi as saying.

In some cases, the target would even simulate the questioning process of the investigation beforehand or ask their relatives working at judicial organs for help, it said.

A local official was very careful with his phone. He bought multiple phone cards, used unregistered phones to talk with his accomplices and met with them at secret places, according to Mao Jianbiao, a local corruption investigator in Hangzhou City of Zhejiang Province.

"When questioning the targets, we must pay attention to our tone and our methods," said Mao, adding sometimes they have to find ways to split up the targets to acquire confession.

"No matter how cunning the fox is, it will never outwit the hunter," said another graft-buster.