Mr Charupong, the Pheu Thai Party leader, said the kamnans and village chiefs are state officials and their attendance in full uniform at the protest rally by the People's Democratic Reform Committee, which has broken the law on several occasions, was an improper act.
Their decision to take sides with the demonstrators would likely result in the public losing faith in them and damage their institutions. As well, their behaviour could be a breach of disciplinary regulations under the 2008 Civil Service Act.
The kamnans and chiefs would be punished if found guilty, he added.
The kamnans and village chiefs from Surat Thani took to the PDRC stage on Saturday night while their 400 colleagues from Chumphon showed up on Tuesday night.
Commenting on Chumphon governor Peerasak Hinmuangkao’s announcement to resign to take responsibility for the incident, Mr Charupong said what had happened was not Mr Peerasak’s fault and he had no need to quit his job.
“But the governor must launch a probe into this matter. If not, he will not have to resign as I will fire him myself," the interior minister said.