In an exclusive interview with NBC News, Briseno, who has helped bury several of the victims, including a relative, described the encounter and how he was prepared to charge the shooter after his wife brought him his gun, but was told by arriving officers to back away.

“Hey, what are you doing,” an officer asked as Briseno began to march toward the school, he said. He recalls responding, “I’m going to go in and try to stop them.”

As police who responded to the 77-minute attack, which ended with 19 children and two teachers dead, face criticism about the delayed confrontation, they’re also being admonished by some city residents, including parents who rushed to the scene, for preventing them from going in.

“I told him that he’s already inside the school,” Briseno said. He said the officer told him to stay back and shut up.