UVALDE, Texas -- Thirty minutes into the deadly siege on her classroom in south Texas, a 10-year-old student did something extraordinary: She picked up a phone.
"Uvalde County 911," was how the call started.
"There's a school shooting at Robb Elementary School," said the hushed voice of a little girl.
"Can you tell me your name?" the dispatcher asked.
"Khloie," she whispered.
From deep inside the siege that would end in the deaths of 19 children and two of their teachers, fourth-grader Khloie Torres -- terrified that the gunman might hear her -- kept law enforcement apprised of what was happening during a series of phone calls. Her repeated pleas for help spanned 46 minutes as officers collected in the hallway outside classroom 112 but did not attempt to end the attack.
"Please hurry, there's a lot of dead bodies," Khloie said. "Please, I'm going to die."
The audio of Khloie's interactions with a police operator obtained and reviewed by ABC News are part of thousands of pieces of digital and documentary evidence collected by investigators.
"Uvalde 365 Presents: Crisis of Command" -- which breaks down the 77 crucial minutes of inaction during the school shooting at Robb Elementary School in Uvalde, Texas -- is now streaming on Hulu.
Khloie's parents are aware that ABC News plans to broadcast portions of her 911 calls and wants them to be heard publicly. Her father, Ruben Torres, said the calls prove that law enforcement should have acted sooner to confront the gunman and end the massacre, the second-worst school shooting in American history.
"I was very proud of her during that call," Torres said. "And when I heard her voice, you know, shedding the tears already happened for me ... and I was like, 46 [expletive] minutes, and you guys did nothing."
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Investigators are now seeking to determine whether some of the cascading errors in the law enforcement response amount to criminal culpability, officials told ABC News in a series of interviews. As part of their probe, investigators are scrutinizing officers' decision to treat the incident as a barricaded subject as opposed to an active shooter.
"The consequences of police inaction at the scene, that is really the whole point of the investigation, and that would be a part of what's presented to the grand jury" when that time comes, said Scott Durfee, a Uvalde County special assistant district attorney working on the case.
Critics say the information 10-year-old Khloie conveyed to a 911 operator should have given officers the knowledge they needed to confront the shooter and end the siege sooner. Twelve minutes after her initial 911 call, Khloie remained on the line with the police operator: "Please help, please my teacher is about to die," she said. "Please hurry. Send an ambulance right away."
"That should have immediately signaled a different course of action," said Eva Guzman, a former state supreme court judge who served on a special committee of the Texas legislature that investigated the Robb shooting.
But questions remain about whether dispatchers were able to convey Khloie's information to the officers making decisions on the scene in the building. Radios and cellular systems were too weak inside the school, crippling the lines of communication.
"The idea that someone so young would know to get on a cell phone and call 911, but maintain that line, [an] open line, and report information that was helpful -- it would've been very helpful, put it that way," said Col. Steve McCraw, director of the Texas Department of Public Safety that is running the criminal investigation.
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It is not clear whether Khloie's information made its way to Pete Arredondo, then-chief of the Uvalde school district police force and the officer making many of the key decisions that day. (Arredondo has denied that he was the on-scene commander and defended his actions.)
"That information should've been taken in by the call taker, should've been immediately relayed to the incident commander, who should have used that information to understand that this was still an active shooter event," said John Cohen, an ABC News contributor, veteran law enforcement official, and an expert in active-shooter response.
Evidence collected by investigators suggests that the city's top police officer on site, Lt. Mariano Pargas, was aware from Khloie's calls that children remained trapped alive inside the classroom.
"The calls you got in from the -- from one of the students," Pargas asked a dispatcher. "What did they say?"
"OK, Khloie's going to be -- it's Khloie," the dispatcher replies. "She's in Room 112, Mariano, 112."
"So how many are still alive?" Pargas asked.
"Eight to nine are still alive," the dispatcher said. "She's not too sure how many are actually [deceased] or possibly injured. We're trying--"
"OK, OK, thanks," Pargas said.
Pargas would later tell investigators that he couldn't recall those details.
Over the course of her 46-minute dialogue with a 911 operator, Khloie stayed calm, at one point telling the 911 operator: "I know how to handle these situations. My dad taught me when I was a little girl."
Her father, a former Marine, said he worked hard to make sure Khloie and her siblings knew how to handle life-and-death emergencies in an age of mass-casualty attacks and exploding gun violence. Ruben Torres said he was so proud that Khloie, that day at Robb, had the presence of mind to wipe blood on herself to make it look like she was shot.
"We had spoken about things like this happening around our nation, give them scenarios, what would they do -- things of that nature," he explained. "I find it amazing that my 10-year-old at that time thought about that."
Khloie continued offering crucial information that critics say should have prompted police action: "Send help for my teachers," she told the dispatcher. "They are still alive but they're shot."
She also served as a conduit for other survivors in the classroom, conveying the police operator's orders to those nearby.
"They are inside the building you just need to stay quiet OK," the dispatcher said.
On the other line, Khloie is heard whispering: "They are inside the building; we just need to stay quiet."
Finally, 46 minutes after Khloie Torres placed her first 911 call, officers from a U.S. Border Patrol tactical unit entered the classroom, shot the gunman, and ended the rampage.
Khloie and nine other classmates from room 112 survived. Now, nine months later, Khloie is in counseling but has not yet returned to school. Her father said her road to recovery has been a struggle.
"She does have survivor's guilt," Ruben Torres said. "I hate to say it, but she really don't care anymore about doing the little things that she used to do, you know? She just wants to be stuck at home."
ABC News' Alexandra Myers, Ali Dukakis, Charlotte Greer, Cho Park, Evan Simon, Gerry Wagshal, Jared Kofsky, Kaitlyn Morris, Kate Holland, Laura Romero, Mike Levine, Pete Madden, Sara Avery, Soorin Kim, Victor Ordonez, Will Kim, Christopher Looft, Ismael Estrada, Nicco Quinones and Tomas Navia contributed to this report.