Within 20 seconds of Officer Stillman getting out of his police car, 13-year-old Adam Toledo had been shot.

The clear image of Adam holding his empty hands in the air moments before the gun was fired has gone viral.

Anger around his death fed into protests this weekend raging against the level of force used by the police in America.

Sky News has gone through footage released by Chicago officials to assess in detail what the videos can tell us about the moment the trigger was pulled.

It reveals how Adam was shot within three seconds of being asked to put up his hands.

We've also analysed the evidence around whether he was holding a gun in the seconds before he was shot.

Audio files and documents released alongside the videos show the officer radioed colleagues to warn that the boy was holding his waistband while fleeing and that police initially documented the youth's age as between 18 and 25.

What does the footage show?

It shows that Adam was not armed when he was shot, as had been initially indicated.

It also shows a gun on the ground, close to the 13-year-old's body.

The police released two edited videos and the independent Civilian Office of Police Accountability (COPA) posted more than three hours of raw footage on its site.

The two edited videos are six and two minutes long. They show what the police believe are the most significant moments in the tapes, as well as annotations and analysis in the shorter clip.

For example, police have labelled a potential object in Adam's hand as a firearm.

The shooting  

The confrontation and shooting happens in just three seconds.

We've analysed the footage frame-by-frame to make sense of it - something not possible for those involved in the incident at the time.  

At 2.38.38am, the police officer instructs Adam to show him his hands. He yells: "Show me your f****** hands."

At 2.38.39am the pair come to a stop.  

Milliseconds later, Adam's right arm moves but is partially hidden by his body – something appears to be in his hand.

At 2.38.40am, Adam raises both hands – empty – into the air. 

In that same second, he is shot.

By 2.38.41am, the 13-year-old is on the floor dying.   

There are only two frames in Officer Stillman's body camera footage where Adam's right hand can be seen and appears to have something in it.  

These are the stills as seen in the footage and zoomed in.

Trying to give a definitive answer if there is a gun in Adam's hand or not in the moments before he is shot is difficult. 

His right hand is only visible for milliseconds. 

The body camera footage shakes because of the officer's movement and is low resolution.  

And, the light in the alley and from the police officer's torch causes unusual shadows.  

In one of the police feeds, we see the gun the police say Adam was carrying.  

The footage is too blurry to compare the shapes exactly, but it is possible to see what appears to be the same lighter colour tip on the gun.  

We can also see his right hand – or an object in his hand – is dark compared to his left hand.

Although this could help confirm he is holding the gun at this time, we see other moments in the video where the light creates the same effect on his visibly empty left hand.

What is clearly visible in the footage is that when Adam raises his hands in the moment before the gun is fired, his hands are empty.  

In the next second, Adam is shot.

What do other feeds tell us about the moments before and during the shooting?

A camera from the Lawndale Christian Health Center at Farragut Career Academy captures the other side of the fence from where Adam was shot.

This footage should reveal how his right arm moves during the moments it is not visible in Officer Stillman's camera or eyeline.  

In the police's edited version, the footage zooms in and appears to show Adam's right arm moving behind the fence. Later, we see police showing a gun on the floor behind that same fence.  

When we broke this down by frame, Adam's arm does not extend far enough to see it move distinctly despite the contrast of his dark jumper against the light brown fence.  

Zooming in, this is the frame where we see Adam's arm most distinctly.

From both the body camera footage and this feed, Adam runs to the end of this gap in the fence, pauses and then turns with his hands up.  

When he pauses, his body stays largely still while his right arm draws back slightly – as seen in the frames where an object appears to be visible.

The view from behind the fence shows his right arm does not extend forward significantly.  

This could suggest if he is holding an object he is more likely to have dropped it rather than thrown an object with force.  

In the feed from another officer's body worn camera, a gun is seen behind the fence.  

We can then map the location of this gun on to the zoomed-in image showing Adam's arm at its most extended.

This shows us how far the gun would have been thrown from where he was stood. 

What happened after Adam was shot? 

Four seconds after the trigger was pulled, Officer Stillman radios his colleagues to report shots had been fired and to request an ambulance.

"Get an ambulance here right now," he says, before trying to assess how hurt the boy was. "Look at me, look at me. Are you alright?" he asks.

In the distressing footage, Adam is rolled on to his back and blood can be seen coming from his mouth. He is unresponsive.

Officer Stillman's body camera footage shows he attempted CPR before switching out with a colleague.

He steps away and walks through the gap in the fence.

At 2.42.08am, his camera shows a gun is on the floor.

In total, 17 police officers attended the scene and contributed body-worn camera footage.

Officer Stillman's footage ends with him sat quietly on the floor, with a colleague by his side.

What else does the footage, audio and documents tell us? 

We compared the raw footage with the police's edited versions.

The raw clips were less clear cut than the annotated analysis in the police's short version suggests, but the police's edited versions are largely a fair representation of the events.

We verified the locations of the cameras which recorded any of the non-body camera videos. This included spots on a residential building and a church.

Also in the COPA release are three recordings of the gunshots allegedly fired by Ruben Roman, which first brought police to the area. Nine gunshots can be heard on the tapes, which were captured by gunshot detection technology used by the Chicago Police Department.

Footage also shows Ruben and Adam walking along together near where the gunshots were heard.

Documents were also included in the release.

In the original case report, police initially wrote that Adam was aged between 18 and 25 years old.

His cause of death is described as a "gun shot wound to the chest" and at the time of writing, he was named as a John Doe (unidentified person).

It also reveals that following the shooting, Officer Stillman was listed as suffering an injury listed as "illness" and appears to have been treated at Rush University Medical Center.

In the tactical response report, it is marked that Adam allegedly:

- did not follow verbal direction

- fled

- gave imminent threat of battery with weapon

- used force likely to cause death or great bodily harm.

How common is it for a 13-year-old to be shot by police in America? 

In 2014, 12-year-old Tamir Rice was shot by police while he held a toy gun. His death was among those which sparked the American Black Lives Matter movement.  

The following year, The Washington Post began to track police shootings. Since 2015, 56 children aged 16 or under have been fatally shot by police in America.  

According to its data, five of those were aged 13 or under. The youngest to have been shot were two six-year-olds: Jeremy Mardis and Kameron Prescott. 

Adam Toledo, who is Latino, is included in this data.

In a crowdfunder for his funeral costs set up by Elizabeth Toledo, his family remember him with the following tribute: "Adam had many dreams that he will never get to live out. Ironically one of his dreams was to become a police officer . It weighs heavy on our hearts to be planning our last goodbyes instead of watching him grow up and live out those dreams."

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling we aim to better explain the world while also showing how our journalism is done.

By Sanya Burgess and Victoria Elms, forensic unit

Pictures: Chicago Police Department and Civilian Office of Police Accountability