When families learned that a gunman had entered Robb Elementary School in Uvalde, Texas, at 11:33 a.m. on May 24, a brutal wait began. Police on the scene did not stop the gunman until well over an hour after he walked into the school, raising questions about whether lives could have been saved if they had acted sooner. Parents who rushed to the school were held outside, where many were forced to wait to learn if their children were safe.

What follows is an account of each of those 78 minutes, as told by video evidence, statements by witnesses and law enforcement, and accounts of 911 calls.