He said the first wounded student he saw, upon entering the emergency room, was Miah Cerrillo, an 11-year-old student who had smeared blood on herself to hide from the gunman. Miah also testified at the hearing via a video feed on Wednesday.

Dr. Guerrero said Miah had been bleeding from a shrapnel wound to her shoulder, and that her face was in shock.

“Sweet Miah,” Dr. Guerrero said, noting that he had known the girl for her whole life and that she had survived major liver surgeries as a baby. Dr. Guerrero grew up in Uvalde and attended the same school, Robb Elementary, as a child. He said he ran outside to tell her parents that she was alive.

Speaking to the House committee, Dr. Guerrero described returning to the emergency room to horrifying sights: two children who he said had been “pulverized” and “decapitated” by bullets.