The Hanoi police announced Tuesday they are investigating the two boys for "accidental disclosure of classified information" during the exams on June 26 and 27.
According to initial findings, one of them smuggled a mobile phone into an exam room in Hanoi on June 26 and took photos of the Math test paper.
He then uploaded the images to the StudyX app for answers but was only able to write two answers from it before being detected.
He did the same thing the next day during the Chemistry and Physics tests. It remains unclear why the proctors did not suspend him after he was first caught.
As the investigation expanded, the police discovered another boy had also used a mobile phone to cheat, taking photos of the Math, History and English test papers and using AI application Gemini.
The proctors discovered the fraud, complained and suspended the student.
Social media users have been querying about a math test paper leak after some of its questions were found circulating on an AI-based math-solving app before the test ended (at 4 p.m. on June 26) as a screenshot photo of the app revealed that the student sent the question at 3:08 p.m.
This has caused concern about the security of examination materials and the integrity of the exam process, and set off an investigation by the Hanoi police.
According to the police, aside from cheating by students, some proctors also failed to properly do their work, allowing breaches to occur.
The police said students involved in this practice would be disqualified and have their test results annulled and could face administrative or criminal action.
Elsewhere, police in the Central Highlands province of Lam Dong announced last Friday they were investigating another male student for "deliberate disclosure of classified information and appropriation of classified documents."
He was caught using high-tech devices to transmit the Literature test questions to a friend outside to answer using ChatGPT.
He bought a bean-shaped wireless earphone and button-sized camera on Facebook, concealed the latter on his body and smuggled it into the exam room along with his phone.
Some 15-20 minutes into the exam he activated the camera, which streamed the questions outside.
Over 1.16 million Vietnamese students took the national high school graduation exam this year.
The exam consists of four subjects, with Mathematics and Literature being compulsory. Students then choose from a variety of elective subjects, including Foreign Language, History, Physics, Chemistry, Biology, Geography, Economic and Legal Education, Informatics, and Technology.
The exam also serves as the primary qualification test for entering university with its scores added to high school grades and potential bonus points to determine admission.