Police in Chicago said Adam Toledo was holding a handgun when an officer shot him in the chest.
Bodycam footage released by US police has revealed a 13-year-old boy was not holding a gun at the time he was shot dead by an officer - despite contrary claims.
Adam Toledo, who was Hispanic, is seen in the shaky footage, captured on March 29, appearing to drop a hand gun at his feet and raising his hands around a second before Officer Eric Stillman fired the fatal shot.
Filmed in Chicago, the release of materials comes at a sensitive time in the US due to the ongoing trial of former Minneapolis officer Derek Chauvin over the death of George Floyd, as well as the recent police killing of another black man, Daunte Wright, near the same city.
On Thursday, Chicago business owners were seen boarding up their store fronts in anticipation of potential unrest - but while there were small marches from outside the police station, there were no signs of widespread demonstrations across the city.
"We live in a city that is traumatised by a long history of police violence and misconduct," said Chicago Mayor Lori Lightfoot.
"So while we don’t have enough information to be the judge and jury of this particular situation, it is certainly understandable why so many of our residents are feeling that all too familiar surge of outrage and pain.
"It is even clearer that trust between our community and law enforcement is far from healed and remains badly broken."
In the footage, Stillman is seen pursuing Toledo on foot down an alley, shouting: "Police! Stop! Stop right (expletive) now!" He adds: "Hands! Hands! Show me your (expletive) hands!" as Toledo appears to slow down.
Toledo then turns toward the camera as Stillman shouts: "Drop it!" and then shoots the teen shortly after. What follows is Stillman calling for an ambulance and telling Toledo to "stay awake". Another officer says he can't feel a heartbeat and begins administering CPR.
According to lawyer Tim Grace, representing Stillman, the officer had no choice but to shoot after he was "faced with a life threatening and deadly force situation," adding that Toledo "had the gun in his right hand".
"All prior attempts to deescalate and gain compliance with all of the officer's lawful orders had failed," he said.
However, Adeena Weiss-Ortiz, the lawyer representing the Toledo family, said the bodycam and other videos "speak for themselves."
She added: "If he had a gun, he tossed it. The officer said: 'Show me your hands.' He complied. He turned around."