There was enough armed police to stop the gunman behind the Texas school shooting just three minutes after he arrived.
Instead, officers equipped with rifles stood and waited in the school hallway for nearly an hour, according to a top official.
Salvador Ramos, 18, went on to kill 19 primary school-age students and two teachers at Robb Elementary in Uvalde.
Colonel Steve McCraw, director of the Texas Department of Public Safety, called the police response “an abject failure.”
Mr McCraw told a Texas Senate committee that Pete Arredondo, the Uvalde school district police chief, decided to put the lives of officers ahead of the lives of children.
“Three minutes after the subject in the West building, there were a sufficient number of armed officers wearing body armour to isolate, distract and neutralise the subject,” he said.
'There's compelling evidence that the law enforcement response... was an abject failure'
“The only thing stopping a hallway of dedicated officers from entering room 111 and 112 was the on-scene commander who decided to place the lives of officers before the lives of children.”
He added: “The officers had weapons, the children had none. The officers had body armour, the children had none. The officers had training, the subject had none.”
The public safety chief began outlining for the committee a series of missed opportunities. Delays in the law enforcement response have been the focus of investigations into the massacre and its aftermath.
“One hour, 14 minutes and 8 seconds. That's how long the children waited, and the teachers waited in rooms 111 to be rescued,” Mr McCraw said.
“And while they waited, the on-scene commander waited for a radio, and rifles. Then he waited for shields. Then he waited for SWAT. Lastly, he waited for a key that was never needed.”
How the police approach played out
The timeline the outlets reported from the documents included footage from inside the school that showed the 18-year-old gunman casually entering a rear door at 11.33 am.
He walked to a classroom and immediately opened fire before barricading himself. Video showed 11 officers entering the school three minutes later, the reports say.
School district police Chief Pete Arredondo called the Uvalde Police Department landline and reported that their suspect had “shot a lot” with an AR-15-style rifle and outgunned the officers at the school, who he said were armed only with pistols, according to the outlets.
Four minutes later, at 11.44 am, body camera video recorded the sound of more gunshots.
At 11.52 am, the first ballistic shield arrived as officers grew impatient to act.
Mr Arredondo struggled to find a key to the classroom door even though no one is believed to have tried opening it, the report claims.
Another officer with a ballistic shield arrived at 12.03 pm and another came with a shield two minutes later.
Around 30 minutes before officers finally breached the classroom door at 12.50 pm, Mr Arredondo is heard wondering aloud if the gunman could be shot through a window.
Only at 12.46 pm did Mr Arredondo tell the tactical team members to breach the door when ready.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know