MANILA, Philippines (AP) — Two people opened fire in a high school in the central Philippines on Monday, killing three students and wounding another five, police officials said.

Two suspects have been taken into custody, police said, one of whom is a student at San Jose National High School in Tacloban city, where the shooting happened, according to police. Both are male and were armed with pistols.

Police investigators were still trying to determine what sparked the shooting in the government-run school, which has more than 1,500 students. Police also deployed forces to beef up security.

“We urge the public to remain calm, refrain from disseminating unverified information and cooperate with authorities by providing any information that may aid the ongoing investigation,” the national police said in a statement.

Crimes involving the use of firearms are prevalent in the Philippines, partly due to the proliferation of unlicensed firearms, but school shootings are relatively rare.