A 15-year-old student opened fire at a private school in the northern Mexican city of Monterrey on Wednesday, hitting a teacher and two other students in the head before killing himself. Another student suffered lesser injuries in the shootings, which were captured on a chilling video posted to social media.

Nuevo León state governor Jaime Rodríguez said the shooter died at a hospital and that the other three victims with head wounds were “fighting between life and death”. The boy wounded in the arm was out of danger.

A video, apparently from the school’s surveillance camera and later posted on social media, showed the teenager quickly and calmly firing what appeared to be seven shots at seated students and a female teacher, some at point-blank range, before shooting himself and collapsing.

Students who had been cowering beneath desks and chairs then fled the classroom, stepping over the shooter to reach the door.

State security spokesman Aldo Fasci said four of the injured, including the shooter himself, had bullet wounds to the head and were in extremely serious condition. He said the student shot the 24-year-old teacher, a 14-year-old girl and a 14-year-old boy in the head, and a 15-year-old classmate in the arm. He then pointed the gun at classmates before shooting himself in the head.



“The classes were going perfectly well, the student stands up from his desk and pulls out a gun,” Fasci said.

He noted that photographs of the shooting had been posted to social media and said the person responsible would be punished. He also appealed to the news media to avoid using the images, which show minors.

Fasci said the shooter had been under treatment for depression, but that the motive was under investigation.

The spokesman attributed it to “the situation that is happening everywhere. The children have access to the internet. This has happened in other countries.”

The website of the American School of the Northeast says it offers bilingual education for students from preschool through ninth grade.

Fasci said the boy had brought the gun from home. It was unclear how he got the .22 caliber pistol into the school. Mexico once had a program to checked book bags at school entrances, but in many places it has fallen into disuse.

“There was a reason why book bags were checked. I think we are going to have to start doing it again,” Fasci said.

Mexico had previously been largely spared the phenomenon of school shootings that has hit the US. In one of the few previous incidents, a 13-year-old student shot a 12-year-old classmate in the head at a Mexico City middle school in 2004, seriously wounding her.

At the height of Mexico’s drug war between 2008 and 2011, schools in northern Mexico were more concerned about the possibility that stray bullets from drug gang gun battles outside schools might enter classrooms. Some schools conducted “duck and cover” drills to combat that possibility.