UVALDE, Texas (AP) – Law enforcement authorities in Texas are facing questions and criticism over how much time elapsed before they stormed an Uvalde elementary school classroom and put a stop to the rampage by a gunman who killed 19 children and two teachers.

Investigators are also unable to say with any certainty whether an armed school district security officer outside Robb Elementary exchanged fire with the gunman, 18-year-old Salvador Ramos, when he first arrived on Tuesday.