Harrowing never-before seen footage shows distraught Uvalde students with blood-soaked hair and clothes fleeing Robb Elementary on school bus - as one girl tearfully tells trooper how she tried not to cry while calling 911 to report mass shooting

Harrowing new footage of a little girl covered in blood amid the Uvalde school shooting has emerged, along with a video of children escaping through classroom windows. 

Robb Elementary School graduate Salvador Ramos, 18, opened fire on young students with an AR-15 on May 24 last year, killing 19 children and two teachers. 

Police have been heavily criticized for their response after it emerged cops waited more than one hour and 14 minutes on the premises before breaching the classroom to engage Ramos. 

Khloie Torres, who was 10 years old at the time, resorted to smearing her classmates' blood over herself to survive the deadly rampage, and fresh footage shows her looking shell-shocked on a bus beside another bloodied pupil.  

Released by Propublica with permission from her parents, the bodycam clip shows the child telling Department of Public Safety Special Trooper Crimson Elizondo that she'd made a desperate 911 call moments before. 

'I was on the phone with the police officer,' Khloie cries, as Elizondo tells her: 'You were so brave'. 

Khloie replies: 'I was trying not to cry', amid the sounds of loud ringing and a child sobbing in the background. 

The child has blood splatter over her clothes and matted into her hair in the upsetting footage. She previously said she considered what her last words would be as the horror unfolded. 

Khloie had been attending class with hero slain teacher Irma Garcia when the shooting took place, as recess had just ended and, being the end of the school year, turned on a movie when things took their awful turn. 

'She told us we were going to go on a quick lockdown,' she told Fox News previously. 'So, my friend, he got up and turned off the TV because that's what we had to do. 

'And, right when she went out to find the key and lock the door from the outside, we heard gunshots.' 

Khloie said that at that moment, Garcia had tried to close the door, but deranged gunman Ramos forced his way inside.

She said the Garcia began to guard the children while her friend and classmate Armory used a friend's phone to try to dial 911.

'When she did that, he started saying, 'you'll die!' Khloie said. 

Garcia started to pleading and begging with Ramos while trying to defend her kids but to no avail.

'He shot my friend and my teachers,' the child recalled. 'And then after that, he said 'goodnight,' and he started shooting everybody.'

Khloie said that Ramos walked around the classroom and shot at everyone he could see before arriving at her.

'He shot the girl next to me, and she said, 'I've been shot!' And, I didn't want to say anything because I didn't want him to come over and shoot me. So, I stayed quiet. He came back and shot her again because she wouldn't be quiet.'

Then, she says, the gunman moved over to the classroom connected to hers and continued to fire. 

Once the gunfire stopped and she heard Ramos move into the hallway, she ran into that classroom to find out whether anyone had survived. 'It's hard because there were bodies everywhere,' she said.

Khloie said she tried to contact the police several times but kept getting told that officers were already at the school.

Ruben Torres, Khloie's father, said that he had been misinformed when the tragedy was going on.

'I heard it from a co-worker of mine telling me that it was a high-speed chase. And, that's common around here, so I didn't think anything of it,' he said. 'If I had known an active shooter was on her campus, I would have left work immediately.'

For now, Torres is focused on making sure his daughter recovers from the horrible things she had to endure.

'It's going to be a long road. This will never go away for her,' he said. 

Another video shows police officers running to a window before helping children escape through it. 

Students can be seen leaping frantically from the windows with the help of cops before bolting across a field. 

Ramos began the deadly rampage after shooting and severely wounding his grandmother in their home earlier that day. 

He broke into Robb Elementary in Uvalde, southern Texas, and remained in an adjoining classroom for more than an hour before members of the United States Border Patrol Tactical Unit fatally shot him. 

Ramos managed to bypass several local and state officers who were in the school's hallways for more than an hour. 

Police officers also waited more than one hour and 14 minutes on the premises before breaching the classroom to engage Ramos. The force was criticized for leaders failing to take charge or set up a command post. 

Some officers struggled with malfunctioning radios, according to ProPublica, but they understood that the shooter was possibly alone inside a room with no victims and failed to act quickly.  

They also cordoned off the grounds, sparking violent conflicts between cops and parents who attempted to enter the school to rescue children. 

Surgeons at the hospital in Uvalde have also suggested that the delay in responding to the shooting may have cost some kids their lives.

It remains unclear exactly how many children were in the classroom when the shooter opened fire, how many were killed immediately and how many were still alive but injured when police arrived.

Uvalde Memorial Hospital received two kids who had died by the time they got to the hospital.

Since the Columbine shooting in 1999, officers across the nation have been advised not to wait for backup and to proceed into the school to find the shooter.

Instructions from the Texas Police Chiefs Association says: 'The first two to five responding officers should form a single team and enter the structure.'

Why that advice was ignored in Uvalde is among the many aspects of the slow response that are now under investigation.

Another is why police falsely claimed at first that the shooter exchanged gunfire with a school resource officer before he even made it to the classroom.