The Oregon man who fatally shot a teenage gunman to end a deadly rampage at an elementary school last week says he was the children's “last line of defense” and that he regrets not arriving soon enough to save them all.

Kaylub Giamanco, whose two daughters attend Silver Rail Elementary, where the Oct. 15 attack occurred, said he feels like he failed the families of those who died.

“I want to apologize for not saving their babies, that’s probably the biggest thing for me right now,” Giamanco told Oregon Public Broadcasting in an interview published Friday. “The gratitude for saving people’s children is awesome. But there were ones that I didn’t save.”

Three children — ages 5, 8 and 11 — and a teacher were killed at the school in Bend, Oregon, last week when a former student there, 16-year-old Griffin J. John II, blasted his way through locked doors with a shotgun and attacked a special needs classroom.…