Con men are now out in action with an offer to increase students' scores in the General Aptitude Test (GAT) and Professional Aptitude Test (PAT).
"No one can do such a thing," Deputy Education Minister Chaiwuti Bannawat said Thursday, "Students and parents should not believe such an offer is possible".
PAT/GAT scores are main criteria in university-admission system.
Some students said they surprisingly received calls from someone who claimed he or she could boost their GAT/PAT scores.
The students said the caller had the information they submitted for GAT/PAT.
Chaiwuti explained that the website of the National Institute of Educational Testing Service (NIETS) had recently been hacked.