An off-duty Border Patrol tactical agent was the first to arrive outside the classroom and “basically said let’s get this done,” according to a U.S. Customs and Border Protection official who spoke on condition of anonymity to share preliminary details of the investigation. “They have not told me they were frustrated,” the official said of other border patrol agents who converged. “But they told me it was hard to discern who was in charge.”…

“We needed the help ASAP for our kids, and it wasn’t there,” Amanda Flores, who said she knew all 21 victims, said at a memorial on Main Street on Friday. “I saw those parents running, wanting to go get their children and the police tackling the parents, and that should have never happened.”…

Chris Grollnek, a retired police officer and active shooter prevention expert, said he was baffled that the school officers waited to confront the gunman while children and teachers were inside the room with him.

“The first responding officer — I don’t care if it’s the deputy dog cartoon guy — he goes in and stops the shooter. That’s just part of the job,” Grollnek said. “You’ve got a ballistic vest. You know what the kids have? Crayons. You are duty-bound to do something. If someone is telling you to stay outside, you disobey that order.”