This story contains descriptions of a violent event that may be confronting.
Bryan Pamonag told 7.30 he was inside a classroom at Banga National High School in the town of Banga, avoiding the September humidity, when loud bangs interrupted the lunch break.
"I looked out the window, and I saw a student carrying a gun," he said. "I looked over at my classmates, and my best friend Chaldean had been shot."
Bryan said the gunman, a student carrying his father's 9mm pistol, was walking towards the classroom while firing.
"I saw him approaching the door while still firing, I crawled toward it to close it," he said. "I kicked him in the stomach and shut our classroom door ... blocking it because he was trying to force it open."
He said he was shot in the hand after the gunman moved to the window and fired at him.
"I saw one of my classmates run out of the room, he was shot three times," Bryan said.
Video posted to social media shows children fleeing the school gates as the shooting unfolded. The gunman died by suicide, an act Bryan said he witnessed.
Photographs from the school show the classroom has been left untouched since the shooting, with a single sneaker still on a desk. A Bible verse has since been painted on the wall outside the building.