[Breaking news update, 12:36 p.m. ET]

While a gunman slaughtered children inside locked adjoining classrooms in a Texas elementary school, a group of 19 law enforcement officers stood in a hallway outside and took no action as they waited for more equipment, a state law enforcement official said Friday.

“The on-scene commander at that time believed that it had transitioned from an active shooter to a barricaded subject,” Texas Department of Public Safety Col. Steven McCraw said.

“From the benefit of hindsight where I’m sitting now, of course it was not the right decision. It was the wrong decision. There’s no excuse for that.”

The decision explains the lengthy wait between when officers first arrived to the school at 11:44 a.m. and when the gunman was finally shot at 12:50 p.m. The tactical team ultimately entered the locked classroom to confront the gunman using keys from a janitor, he said.

[Previously published story, 11:51 a.m. ET]

Texas law enforcement officials are facing doubts and sharp questions Friday about their response to the mass shooting at an elementary school, while the traumatized children who were stuck in the school with the gunman explained how they survived.

Nineteen students and two teachers were slaughtered Tuesday at Robb Elementary School in Uvalde before a federal tactical team killed the gunman, ending the deadliest US school shooting in almost a decade.

Officials initially praised the law enforcement response and noted that the carnage could have been worse. But in a press conference Thursday, Victor Escalon of the Texas Department of Public Safety (DPS) said there were no officers outside the school to try to stop Salvador Ramos, 18, from entering an unlocked door in the first place, contradicting authorities’ earlier claim Ramos was “engaged” by a school resource officer as he entered.

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Escalon also offered a timeline that showed police arrived at the school 16 minutes after the gunman crashed a vehicle in a ditch nearby. He said officers encountered the gunman in the school at 11:44 a.m. — but the suspect remained inside a classroom with children and teachers for about an hour before a tactical team forced their way in and fatally shot him.

The lengthy standoff raises questions as to whether police followed proper protocol, established since the Columbine school shooting of 1999, to end the threat as quickly as possible because fatalities occur in seconds to minutes.

“We deserve to know what happened. These parents deserve to know what happened,” state Sen. Ronald Gutierrez, whose district includes Uvalde, told CNN on Thursday.

“I know there was a failure here,” Gutierrez added, noting he has seen video of law enforcement entering the building and the standoff. “And I feel in this situation, standing back was not the thing to do.”

DPS is set to hold a press conference to give updates at noon ET.

The shooting in Uvalde is the deadliest school shooting since the 2012 Sandy Hook massacre and at least the 30th shooting at a K-12 school in 2022. The attack came less than two weeks after a racist mass shooting in Buffalo, New York, and has left Americans grieving yet again and many renewing calls for gun law reform.

Surviving children describe what happened inside

While those questions remain unanswered, children who survived the shooting described what happened inside the school during the mayhem.

To survive the nightmare, Miah Cerrillo, 11, smeared her friend’s blood all over herself and played dead, she told CNN.

Miah and her classmates were watching the movie “Lilo and Stitch” when teachers Eva Mireles and Irma Garcia got word of a shooter in the building. One teacher went to lock the door, but the shooter was right there — and shot out the door’s window, Miah said.

As her teacher backed into the classroom, the gunman followed. He then looked a teacher in the eye, said “Goodnight,” and shot her, the girl recalled.

And then he opened fire, shooting the other teacher and many of Miah’s friends. Bullets flew by her, Miah said, and fragments hit her shoulders and head.

The gunman next went through a door into an adjoining classroom. Miah heard screams and more gunshots. When the firing stopped, the shooter started playing music that was “sad, like you want people to die,” the girl said.

Scared he would come back to kill her and her few surviving friends, Miah put her hands into the blood of a slain friend lying next to her and smeared herself with it, she said.

The girl and a friend managed to grab a dead teacher’s phone and call 911 for help, she said. She told a dispatcher, “Please send help because we’re in trouble.”

The pair then lay down and played dead.

Another student in a different classroom, 10-year-old Jayden Perez, said when he and his classmates heard gunfire, his teacher locked the door and told them to “hide and be quiet.”

Jayden said he was hiding near the storage area for backpacks during the shooting. Others in his class were under a table. The entire time, he wondered what was going to happen to them.

“It was very terrifying because I never thought that was going to happen,” he told CNN. “(I’m) still sad about some of my friends that died.”

He does not want to go back to school again.

“No, because after what happened. I don’t want to. I don’t want anything to do with another shooting or me in the school,” he said. “And I know it might happen again, probably.”

Gunman entered school unobstructed, officials says

Investigators are still piecing together a timeline of the carnage, Escalon, DPS’ South Texas regional director, said during a news conference. “With all the different agencies that are involved, we’re working every angle that’s available,” Escalon said. “We won’t stop until we get all the answers that we possibly can.”

After shooting his grandmother in her home, Ramos drove to Robb Elementary, where he crashed his truck in a nearby ditch, DPS Sgt. Erick Estrada said. It’s unclear why he crashed.

The shooter then fired at two witnesses across the street before climbing a fence, moving toward the school and shooting at the building, according to Escalon.

There were no officers outside the school to stop Ramos, who “walked in unobstructed initially,” Escalon said Thursday. Earlier information about a school resource officer engaging the gunman was “not accurate,” he said.

Ramos got into the building through an apparently unlocked door at 11:40 a.m., Escalon said. That door is normally locked, “unless you are leaving to go home on the school bus,” former principal Ross McGlothlin told CNN.

Inside the school, the shooter barricaded himself inside two adjoining classrooms and fired more than 25 times, Escalon said.

At 11:44 a.m., law enforcement arrived and entered the school.

What law enforcement did inside and outside the school

What happened in the hour between their arrival and the gunman’s death remains murky.

At least seven officers rushed into Robb Elementary within four minutes of the shooter’s arrival, DPS spokesperson Chris Olivarez told CNN. Three officers went in the same door the shooter used and four used a different entrance, Olivarez told CNN.

When they confronted the shooter, he fired at them and they took cover. Two responding officers were shot; their injuries were not life threatening, said Uvalde Police Chief Daniel Rodriguez.

“It is important for our community to know that our officers responded within minutes” alongside school resource officers, he said.

Officers then called for more tactical teams and resources, such as body armor, while they worked to evacuate teachers and students, Escalon said. About an hour later, a US Border Patrol tactical team entered and killed Ramos, he said.

When asked for more details at a news conference about what exactly responding officers were doing in the hour-long period, Escalon declined to provide further information.

Outside the school, chaos and confusion reigned as distraught parents showed up and implored law enforcement to force their way in and kill the gunman. One father even asked officers to give him their gear, he said.

“I told one of the officers myself, if they didn’t want to go in there, let me borrow his gun and a vest and I’ll go in there myself to handle it. And they told me no,” Victor Luna told CNN. His son survived.

Instead, officers held parents behind yellow police tape, refusing to let them enter as crying and screaming echoed around them, several videos show. After about an hour, a US Border Patrol tactical team forced its way into the classroom and fatally shot the gunman, Escalon said.

Members of the US Marshals Service can be seen in video holding back parents who pleaded to enter the school. US Marshals said in a statement they were called to the school at 11:30 a.m. and arrived about 40 minutes later from Del Rio, about 70 miles away.

The first deputy US Marshals to arrive entered the school to assist the Border Patrol tactical team already engaging with the shooter. The deputies also rendered aid to victims. Other deputies were asked to secure the perimeter around the school, but never arrested or placed anyone in handcuffs, the agency said.

“Our deputy marshals maintained order and peace in the midst of the grief-stricken community that was gathering around the school,” the agency said.

Grieving community reckons with aftermath

Days after the massacre, the residents of Uvalde are still saturated in grief. The final victims’ remains were returned Thursday night to families. Six people were still hospitalized Thursday, including the shooter’s grandmother, who was shot in the face.

And the devastating news continued to pour in Thursday as word spread that the husband of a slain teacher died of a heart attack brought on, his family said, by a broken heart.

Joe Garcia’s death was confirmed by the Archdiocese of San Antonio. Irma Garcia was a fourth-grade teacher and had been married to Joe for over 25 years, according to a GoFundMe campaign posted by her cousin.

For survivors, trauma is sinking in. Edward Timothy Silva, a second grader who hid behind desks in the dark at the school as he heard loud noises in the distance now wonders: “Does he have to go to school next year,” his mother Amberlynn Diaz said.

“And I just don’t want him to be afraid of school,” she said. “I want him to continue learning and not be scared of going back to school. I want him to have a normal life again.”

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