Vietnamese authorities are continuing to investigate irregularities in the 2026 National High School Graduation Examination after a teacher at Tuyen Quang High School for the Gifted was arrested in connection with unusually high mathematics scores recorded at the school's examination center.

At a press conference on July 6 reviewing policing activities during the first half of 2026, Tuyen Quang Provincial Police confirmed that the criminal investigation remains ongoing and that additional information will be released once investigative procedures have been completed.

The case has attracted nationwide attention after an exceptionally high number of perfect mathematics scores were concentrated within a single group of candidates at one examination center.

Police: Investigation still underway

Responding to questions from journalists, Colonel Hoang Van Manh, Deputy Director of Tuyen Quang Provincial Police, said the provincial Investigation Police Agency is continuing to verify all aspects of the case in accordance with Vietnamese law.

One of the main issues raised during the press conference concerned the role of Nguyen Ha Duy, a teacher at Tuyen Quang High School for the Gifted, and whether investigators were expanding the inquiry to other individuals involved in the examination process.

Lieutenant Colonel Pham Thanh Son, Deputy Head of the Internal Political Security Division, said only preliminary findings had been made public.

"The investigation is continuing under the direction of the Ministry of Public Security, the Tuyen Quang Provincial Party Committee, the Provincial People's Committee and Tuyen Quang Provincial Police," Son said.

He added that because of procedural requirements and the sensitive nature of the investigation, authorities could not disclose additional details at this stage.

"When the investigation has concluded and the legal conditions for releasing information have been met, Tuyen Quang Provincial Police will officially provide updates to the media," he said.

Teacher placed under emergency arrest

Earlier on July 6, the Tuyen Quang Provincial People's Procuracy approved an emergency arrest warrant for Nguyen Ha Duy, born in 1998, a teacher at Tuyen Quang High School for the Gifted.

He is being investigated in relation to the results of the 2026 National High School Graduation Examination at the school's examination center.

The arrest followed an emergency detention order issued by the provincial Investigation Police Agency on the afternoon of July 5.

According to Vietnam's Criminal Procedure Code, emergency detention is an initial preventive measure that allows investigators to temporarily restrict a person's liberty while collecting evidence.

If investigators subsequently establish sufficient legal grounds, they may request prosecutorial approval to convert the detention into an emergency arrest.

Legal experts note that this progression reflects additional evidence gathered during the early stages of an investigation. However, neither emergency detention nor emergency arrest constitutes a determination of criminal guilt.

Under Vietnamese law, only a legally effective court judgment following investigation, prosecution and trial can determine criminal responsibility.

Extraordinary concentration of perfect scores

The investigation began after examination data revealed a statistically unusual pattern in mathematics results.

According to figures previously released by authorities, 147 of Tuyen Quang Province's 154 perfect scores in mathematics were recorded within a consecutive block of 328 candidates assigned sequential examination numbers.

Those candidates achieved an average mathematics score of 9.55 out of 10, prompting authorities to initiate a comprehensive review.

The unusually high concentration of perfect scores has become the central focus of the investigation.

Ministry task force finds no irregularities in marking process

On July 2, Vietnam's Ministry of Education and Training established a special inspection task force to review all matters related to the mathematics examination administered by the Tuyen Quang Examination Council.

The task force comprises representatives from the Ministry of Education and Training and the Ministry of Public Security, working under the direct supervision of Deputy Minister Pham Ngoc Thuong, who also chairs the National Steering Committee for the 2026 National High School Graduation Examination.

According to the ministry, inspectors have not found any irregularities in the printing, transportation, storage or marking of examination papers.

However, following statistical analysis and preliminary verification, the task force concluded that the mathematics results at the examination center hosted by Tuyen Quang High School for the Gifted were sufficiently unusual to warrant further investigation.

The ministry said particular attention is now being directed toward the examination invigilation process at the test center.

Authorities have not announced whether additional suspects are under investigation, whether any examination results may ultimately be affected, or when the investigation will conclude.

The inquiry remains ongoing.

Vu Mung - Duc Phong