Speculation has run rampant in the media ever since Tian Fengshan, former minister of land and resources, was removed from the post last month.

Citing various sources, media reports have speculated that Tian was involved in several corruption cases in Northeast China's Liaoning Province where he used to work as the governor, and is also believed to be accountable for serious irregularities in land use and transfers as the minister.

A notice from the State Council said Tian was found to "have serious disciplinary problems and is under investigation." It stopped short of giving more details.

It is taking time for the Central Commission of Discipline Inspection, the Party's anti-corruption organ, to finish the investigation and publicize the results, which will decide whether Tian's case will be transferred to the legal department.

So far Tian's problems remain a question mark, but one thing is sure: He did commit something wrong. Without certain evidence, the State Council would not have made the decision to sack him.

Tian became the latest provincial-level official dealt with by the central disciplinary department this year, following Cheng Weigao in Hebei Province and Liu Fangren in Guizhou Province.

Once again, it shows that the central government will not tolerate corrupt activities, even when high-ranking officials are involved. The tough, no-compromising attitude has no doubt shored up the public's trust and confidence in the government's anti-corruption campaign.

The consecutive falls of high-ranking officials, however, also expose loopholes in the current supervision system on government officials, especially those maintaining high and important posts.

These corrupt officials should be blamed for relaxed self-discipline. A lack of a highly efficient supervision system, however, makes it possible for them to abuse public power to satisfy their personal greed.

Due to a lack of effective supervision, problems involving high-ranking officials cannot be sorted out in a timely fashion. They are usually sealed for a long time until greater losses to the State have been incurred.

Worse, some could even go smoothly through the examination procedure for promotion and be moved to higher posts.

In the ever-intensifying campaign against corruption, more emphasis should be laid on the systematic building and implementation of a well-functioning supervision system.