The Ministry of Agriculture and Cooperatives has set up a committee to investigate bribery claims at the top of the Royal Irrigation Department (RID). The ministry said wrongdoers will face legal action if they are found guilty.
Thongplew Kongjun, former chief of the RID, who is now the ministry's permanent secretary, was appointed as head of the committee probing the case.
According to news reports, a person with close ties to a politician paid about 400 million baht to receive a high position at the irrigation department. It is unclear what evidence has come to light.
The reports were published at the same time as a selection process is underway for the vacant RID position left by Mr Thongplew when he joined the ministry.
The RID's selection committee is considering two candidates for the top position.
When complete, the finalist will be nominated and his or her name sent for approval by the cabinet next week.
Thana Cheeravinij, secretary to agriculture minister Chalermchai Sri-on, said Mr Chalermchai insisted he is not involved in any position-buying scheme.
Mr Thana said the RID head selection committee is headed by Mr Thongplew, the ministry's permanent secretary, and other high-ranking officials, noting the minister is not involved in the selection process.
"To make it clear, the minister has ordered the setting up of the probe committee to clear the bribery claims," he said.
"However, if there is pressure from an outsider regarding the case, the committee will investigate the case, regardless of whether or not the case involves the bribery claim," Mr Chalermchai's secretary added.
Mr Thana said that anyone -- politician or otherwise -- found to be involved in any bribery scheme will be punished under the law.