UVALDE, Texas—The gunman behind the mass shooting at an elementary school here lingered outside the building for 12 minutes firing shots before walking into the school and barricading in a classroom where he killed 19 children and two teachers, authorities said in a news conference Thursday laying out a new timeline of events.
Victor Escalon, a regional director for the Texas Department of Public Safety, said he couldn’t say why no one stopped the deceased gunman, 18 year-old Salvador Ramos, from entering the school during that time Tuesday. Most of the shots Ramos fired came during the first several minutes when he entered the school, Mr. Escalon said.