Some senior officials were involved in cheating in an examination to recruit teaching assistants nationwide in January, the Department of Special Investigation (DSI) has found.
A source from the DSI team handling the case said the agency's probe indicates Education Ministry executives in Bangkok were linked to the case.
The ministry's order to switch the exam organiser from the Educational Service Area Offices to the Office of Basic Education Commission (Obec) was suspicious. The order could be made only by senior officials at the ministry, the source said.
The new orders also demanded the organisers notify how many assistant teachers they wanted, and in what subjects, to the central administration.
This would have allowed the cheating network to arrange applicants in line with the area's needs, the investigator said.
The cheating was mainly carried out by the central administration's officials as the exam papers involving 30 major subjects had been obtained by some applicants before they sat the exam, the investigator added, citing the DSI's initial findings.
Thanin Prempree, director of the DSI's corruption prevention and suppression centre, said the DSI was still unauthorised to fully investigate the case.
The DSI's special case committee will decide whether to take up the case as a special case on Wednesday, he said.
If the panel approves it, extensive investigations will be carried out. The initial probe found nine irregular practices in the exam, he said.
According to the DSI, exam papers and answers were leaked in four northeastern provinces _ Khon Kaen, Udon Thani, Yasothon, and Nakhon Ratchasima _ and many applicants used imposters to sit the exam in their place.
The civil servants who abused their power will be held accountable by the National Anti-Corruption Commission, Mr Thanin said.
Some other state officials, who were not directly linked to the exam, were also found to be involved with the cheating, Mr Thanin said.
He said the DSI found some school headmasters handed out the answers to exam applicants, while other officials provided training for exam-takers on how to use electronic devices to get answers during the test.
Mr Thanin said the DSI has started tracking the network's money trail. It may take some time because the money is commonly paid in cash, he said.
Department chief Tarit Pengdith said the investigation found links between the central administration, the regional offices and applicants in the cheating scam.