The hero dad who killed Oregon elementary school shooter Griffin John recalled hearing children “pleading for their lives” as the massacre unfolded.

Kaylub Giamanco, 36, recalled the deadly series of events at Silver Rail Elementary School after he saw John, 16, bust into the building with a shotgun last Thursday in a sit-down interview with Oregon Public Broadcasting.

Giamanco, a carpenter and dad of two girls who attend the school, was driving home to eat leftovers with his wife during his lunch break when he saw John firing a gun twice at a red pickup truck, then at a woman mowing the school’s lawn before hopping a fence to begin his deadly rampage.

“That’s when panic fled into my brain, and that’s when I opened my center console,” Giamanco told the outlet of the moment he reached for his .40 caliber handgun.

“I just was in full panic, like, ‘No, there’s children, there’s babies in there.’ I told my Siri to call 911,” he said, though he didn’t stay on the line to answer the dispatcher’s questions.

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He then rushed from a wallball court to the building on his hands and knees and heard “children pleading for their lives” as John fatally shot three children and a teacher.

“That’s when I started hearing children pleading for their lives and then I started hearing gunfire and I just started army crawling faster and faster and I told myself this is probably the last thing that I’m ever going to do.”

John also critically injured a 7-year-old girl in a wheelchair and a teacher.