Dong Yong'an, the director of the transport department of Central China's Henan province, is under investigation for possible disciplinary violation, government sources confirmed on Thursday.

If the allegations of corruption against Dong are found to be true, he will become the fourth official to be dismissed from that position. This has triggered heated online discussion that being a transport chief is a "high-risk" job that is easily susceptible to graft.

Dong has been placed under shuanggui, a procedure in which a Communist Party of China (CPC) member is asked to confess to wrongdoing at a stipulated time and place, the Hong Kong-based Bauhinia Magazine reported on its website on Wednesday.

A source within the Henan provincial discipline authority confirmed with China Daily on Thursday that Dong is under investigation, but would not give details.

Dong's resume and media reports, previously available at the website of the Henan provincial transport department, had disappeared when China Daily checked it on Thursday.

Dong was appointed the Henan provincial transport chief in March 2008.

Before that, his three predecessors had been found guilty of corruption.

In October 1997, then Henan provincial transport chief Zeng Jincheng was sentenced to 15 years in jail for taking bribes of more than 200,000 yuan ($30,179), according to media reports.

Zeng's successor, Zhang Kuntong, was found guilty of taking bribes and embezzlement in March 2001, and was sentenced to life in prison. Shi Faliang, who took the post from Zhang, was also sentenced to life in jail in August 2006 for taking bribes of more than 19 million yuan, according to court documents.

Ironically, all three officials before Dong had made their claims about "clean governance" while in the job. Zeng had even written a "blood letter" to the Henan provincial Party committee to show his anti-corruption stance.

The latest exposure of Dong's possible corruption has triggered heated discussion online, and many netizens have labeled transport officials as "high-risk" as they usually have too much power, especially in road construction and project contracts.

Another high-risk area seems to be the food and drug safety sector.

The discipline watchdog of the CPC said on Thursday that Zhang Jingli, former deputy director of the State Food and Drug Administration (SFDA), has been discharged from public employment for serious violations of discipline and law.

Zhang was also expelled from the Party, the Central Commission for Discipline Inspection of the CPC said seven months after it announced Zhang was "under investigation for suspected disciplinary violations".

Zhang, 56, became deputy director of the SFDA in 2003. He was still serving in that position in 2007 when former SFDA director Zheng Xiaoyu was executed for taking 6.49 million yuan in bribes and dereliction of duty.

Zheng's downfall led to the exposure of more corrupt officials in the food and drug system.