The Department of Special Investigation (DSI) says it has found clear evidence of cheating in its preliminary probe into the nationwide assistant-teacher recruitment examination.
Department chief Tarit Pengdith said the Education Ministry will reveal its detailed findings today.
The DSI will recommend the ministry scrap the results of the exams in areas where clear evidence of cheating was found, Mr Tarit said.
The exam was held to recruit 2,000 assistant teachers nationwide.
The DSI would send the results to Deputy Education Minister Sermsak Pongpanit, who could then make them public.
Mr Tarit said the DSI had detected three methods of cheating.
One was to have people pose as applicants and sit the exam so they could leak the answers to real applicants in the same room via hidden electronic devices.
Another was to leak exam papers and answers to applicants ahead of the test, and the third method was to have imposters sit the exams.
Previously, Thanin Prempree, director of the DSI's corruption prevention and suppression centre, said initial findings suggested that cheating in the Jan 13 exam took place in Udon Thani, Yasothon, Chaiyaphum and Khon Kaen.
An in-depth investigation should be carried out after the DSI's special case investigation committee approves a request to treat the exam fraud allegation as a special one, Mr Tarit said.
With that approval, the department can deploy special measures to dig deeper into the allegations, such as the suspects' money trail and how each of them is connected in the alleged cheating network.