A rare shooting at a public high school in the central Philippines that left three students dead and seven injured has gripped the country amid concerns over campus safety and the mental well-being of young people.

Two Grade 9 students, aged 14 and 15, were arrested over the incident at the San Jose National High School in Tacloban City, Leyte province.

The weapons involved were a .38 revolver and a 9mm pistol – the latter of which was traced to a police officer who was one of the suspects’ aunts. Authorities said the .38 revolver was linked to a security agency in Cebu City.

An initial investigation by the Philippine National Police pointed to a grudge from school bullying as the cause of the violence.

“We have taken custody of the 2 CICL [Child in Conflict with the Law] suspects … initially, it appears that the motive of the crime was grudge for school bullying,” national police spokesman Colonel Allen Rae Co said at a media briefing.

A report from the Philippine Daily Inquirer quoted an anonymous teacher who described one of the suspects as “quiet [and] socially withdrawn”, and had been held back a year due to poor academic performance.