Education authorities from the central province of Nghe An asked local police, on Wednesday, to help investigate a schoolgirl being beaten by three others.
The attack was recorded on a mobile phone and posted online.
The 31 second video long shows a girl pulling another girl by her hair to the middle of the street. The victim is then pushed down onto the street and beaten by two others.
She was kicked, repeatedly, on the body, head and face. One of the girls, later identified as Nguyen Thi Huong Tra, a twelth-grader at Huu Nghi Private High School who just won two gold medals in national Karate competitions, was identified as an attacker.
The victim has been identified as Nguyen Thi Ha Nhu, a 12th grader at Ha Huy Tap High School in Vinh, the capital city of the province, according to Nguyen Dinh Cuong, vice principle of the Ha Huy Tap.
Tra said the two other girls, Huyen and Van Anh are her friends and former students of the Nguyen Truong To Private High School and Thai Lao High School. Both had been expelled from school, Saigon Tiep Thi said Friday.
Nhu has been questioned by school officials but said she didn't know why she was beaten.
The video first circulated among students in the province before being posted on the Internet.
Nguyen Trong Hoan, deputy office chief and spokesman of Nghe An Department of Education and Training, said the department will punish the students strictly after the police complete their investigation.
In March, Hanoi education department also had to ask the police to investigate an online video clip showing a girl attacking a fellow student.
Several such clips have gone on the Internet before that and the most fights started from minor disagreement.