Manila, Philippines — Two students armed with hand guns opened fire in a high school in the central Philippines on Monday, killing three fellow students and wounding another seven, police said.

The suspects, aged 14 and 15, were arrested. The suspects and victims were students of the San Jose National High School in Tacloban city, southeast of Manila, where the mid-morning shooting happened, regional police chief Brig. Gen. Jason Capoy said.

An investigation was underway to determine the cause of the shooting in the government-run school, which has more than 1,500 students. Capoy said the suspects, who were close friends, said in initial questioning that they were bullied in school. He didn't elaborate.

They have no criminal records, Capoy said. They managed to bring the guns into the campus because there was only one guard on duty at multiple entrances and exits, he added.

National police spokesman Allen Rae Co told a media briefing a 9 mm pistol used in the shooting was registered to a policewoman in the region and she was taken into custody, French news agency AFP reported. Co said the other weapon used in the shooting, a .38 caliber revolver, was registered to a security agency in Cebu City in the central Philippines.

It wasn't clear how the suspects got the weapons, police said.

Over 40 empty shells were found at the scene, police added.

"The suspects barged into two rooms because after the shooting in the first, the children scampered and the suspects apparently ran after some victims into another room," Capoy told reporters.

Most of the dead and wounded were female students, he said.

In a video posted online, students hiding under desks in a shut classroom can be heard screaming and weeping as gunshots could be heard outside. Some called their mothers. Other videos show visibly terrified students streaming out of the school campus, some holding and embracing each other.

One of the suspects was arrested in the school after the attack but the second fled and hid in a house nearby. He was found by police who were alerted by residents, police said.

President Ferdinand Marcos Jr. ordered a thorough investigation of the shooting and asked law enforcement to boost security in all schools, workplaces and public areas, Communications Undersecretary Claire Castro said.

"The president was saddened by this incident. Anybody, especially the parents of the victims, will feel sad and terrified," Castro said.

The national police have urged the public to remain calm and cooperate with authorities by providing any information that may aid the ongoing investigation.

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.

In 2022, a man armed with pistols opened fire in an upscale university in the Manila metropolitan area ahead of a graduation ceremony, killing a former Philippine town mayor with whom the suspect had a long-running feud and two others in the brazen attack. The gunman was arrested.