The incident took place last week at Van Phu Secondary School in Tuyen Quang Province and was videotaped.
The video was then spread on social media.
As seen in the video, more than 10 students of a seventh-grade class forced a female teacher to a corner of a classroom, which they locked, to scold her.
At times, they threw objects at her and pointed at her with sticks and hand fans as they screamed at her.
The teacher did not make any attempts to stop them.
Speaking to VnExpress on Tuesday, Bui Xuan Luong, chairman of Van Phu Commune in Son Duong District, home to the school, said authorities received a report about the case from the school on Dec. 1.
He said both sides (the teacher and the students) should be blamed for the incident.
Luong said the teacher is notorious for "using bad and inappropriate language" when speaking with students.
The school has recently reprimanded her for such behavior.
"Students have already disrespected her and on the day of the incident, she also spoke to the kids inappropriately, which triggered them to treat her like that," he said.
Local police invited the students involved in the case, their parents, and the music teacher to the school for a meeting on Dec. 2.
The teacher did not show up.
Another meeting with only the teacher was scheduled on Tuesday for further elaborations on the case.
After that, the school and authorities will propose solutions to the problem.
In the meantime, the students have been made to write an incident statement and submit it to the school.
Since the incident, they have continued attending school as normal.