ITV News Reporter Hamish Auskerry reports on events from the convention of America's biggest gun lobby, held in the same state as the shooting
Texas police have said "the wrong decision" was made in the Uvalde school shooting, as it emerged officers waited an an hour before entering the classroom and shooting the gunman.
Nearly 20 officers were in a hallway outside the classroom for more than 45 minutes before US border patrol agents used a master key to open the locked door. Once inside they shot dead 18-year-old gunman Salvador Ramos at around 12.50pm.
Ramos killed 19 children and two teachers.
Texas Department of Public Safety Director Steven McCraw said at a news conference that the commander had assumed the gunman was barricaded inside and that it was no longer an active shooter situation.
What mistakes did the police make? ITV News Correspondent Geraint Vincent reports on what we know so far
But he added "it was the wrong decision," to wait so long as "there were in fact children in the classroom and it was in fact still an active shooter situation."
Mr McCraw said there was a barrage of gunfire shortly after Ramos entered the classroom where he was killed, but that shots were “sporadic” for much of the 48 minutes officers waited outside the hallway.
He said investigators do not know if or how many children died during those 48 minutes.
Throughout the attack, teachers and children repeatedly called 911 asking for help, including a girl who pleaded, “Please send the police now,” Mr McCraw said.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know
Texas Department of Public Safety Director Steven McCraw gave a timeline of events:
11.27am: The exterior door Ramos would use to enter the school is propped open by a teacher.
11.28am: Ramos's car crashes outside the school. Two men from a nearby funeral home run to the scene. Ramos begins shooting at them, and they run back to the funeral home to call 911.
11.31am: The shooting begins outside the school at the same time patrol vehicles arrive at the funeral home.
11.32am: A teacher runs to grab her phone.
11.33am: Ramos enters the school. He begins shooting at rooms 1-11 or 1-12.
11.35am: Officers enter using the the same door.
11.41am: Ramos fires again.
12.03pm: Officers continue to arrive in the hallway, as a 911 call is made from inside the classroom.
12.15pm: More officers arrive outside with shields.
12.16pm: Another child makes a 911 call from inside the classroom, and indicates as many as nine pupils are still alive.
12.50pm: Officers enter the classroom with a key and Ramos is killed.
Later on Friday night, the National Rifle Association (NRA) convention went ahead in Texas - despite criticism at its timing and proximity to the attack.
Former president Donald Trump addressed the USA's biggest gun lobby, appearing to suggest "broken homes" and "bad behaviour" at school were behind mass shootings like the one in Uvalde.
Mr Trump decided to open his speech by reading out the names of the 19 children and two teachers killed in the attack. His critics saw it as tasteless and inappropriate given his fierce support for the NRA and for the right of even teenagers to buy assault rifles.
After each name, a bell rang out.
Donald Trump places the blame for mass shootings with 'broken homes'
What's been the reaction to the details emerging about the police response?
Friday's update on the timeline came only after questions mounted over the amount of time it took officers to enter the school to confront Ramos, and after authorities declined to explain why they had not been able to stop him sooner.
"They say they rushed in," said Javier Cazares, whose fourth-grade daughter, Jacklyn Cazares, was killed in the attack, and who raced to the school as the massacre unfolded: “We didn’t see that.”
During the massacre, frustrated onlookers urged police officers to charge into the school, according to witnesses.
“Go in there! Go in there!” women shouted at the officers soon after the attack began, according to Juan Carranza, who watched the scene from outside a house across the street.
He added officers should have entered the school sooner: “There were more of them. There was just one of him."
Michael Dorn, executive director of Safe Havens International, which works to make schools safer, cautioned that it’s hard to get a clear understanding of the facts soon after a shooting.
“The information we have a couple of weeks after an event is usually quite different than what we get in the first day or two. And even that is usually quite inaccurate,” he said.
Mr Dorn added that for catastrophic events, “you’re usually eight to 12 months out before you really have a decent picture.”