At least four people were killed and nine injured in a shooting early Tuesday at Ateneo de Zamboanga High School in Zamboanga City in the southern Philippines, including the alleged shooter, local media outlet The Manila Times reported.

The incident occurred shortly before classes were due to begin, police said.

The National Bureau of Investigation said two students and two security guards were killed and nine others were injured in the shooting. The identities of the victims have not been released.

The shooter was identified as male and a fourth-year high school student whose father reportedly worked at the Zamboanga City Customs Office, according to the report.

Authorities said the suspect brought a pistol and a rifle to the campus and opened fire inside a classroom “without apparent provocation.”

The alleged shooter and the victim were both students at the Jesuit-run private school, said Mayor Khymer Adan Olaso.

Video showed students fleeing a school building as a gunshot was heard.

Police and investigators remain at the scene as authorities determine the motive and examine possible security lapses.