A shooting at an American school in the north-eastern Mexican city of Monterrey has left at least five people injured, officials say.
A 15-year-old student suffering from depression opened fire, injuring a teacher, three students and himself, a state spokesman said.
The nationalities of those shot at the Colegio Americano del Noreste were not clear. Reports said the injured were in a serious condition.
School shootings are rare in Mexico.
Aldo Fasci, a security spokesman of Nuevo Leon state, called the incident unprecedented. He said the motive was under investigation.
A video showed the gunman shooting the 24-year-old teacher and the students, two aged 14 and one 15, the spokesman said. He then shot himself.
“[This] is result of a situation that is happening everywhere. The children have access to the internet. This has happened in other countries,” he said.
Mr Fasci said it was not clear how the student got the gun into the private bilingual school, which includes pre-school, elementary and high school classes.
He added that Mexico once had a system in place to check student bags but it ended after parents complained.