UVALDE, TexasCommunity members including relatives of students expressed anger and frustration Thursday about the time it took to end the mass shooting at an elementary school here, as police laid out a timeline with new details about their response.

Victor Escalon, a regional director for the Texas Department of Public Safety, said in a briefing that the now-deceased gunman, 18-year-old Salvador Ramos, lingered outside Robb Elementary for 12 minutes firing shots before walking into the school and barricading himself in a classroom where he killed 19 children and two teachers.