A black college football player who crashed a car into a dealership was shot dead by a white trainee police officer as he responded to a report of a burglary.
Christian Taylor (19) from Arlington, Texas, was killed by Officer Brad Miller who was attending the scene with the colleague who was training him.
Other officers attended but were setting up a perimeter around the scene when the shooting occurred.
Police said they were responding to a report of a break in at the Classic Buick GMC in Arlington, about 16km west of Dallas.
They have now said that Officer Miller, aged 49 from Dallas, only graduated from police academy in March and had never fired his weapon before.
He had no experience of policing before joining the Arlington force and had been working under the supervision of a training officer since leaving the academy.
Mr Taylor, who died at the scene, was found to be unarmed. A police investigation is now under way.
It is the latest in a series of shootings of black men by white police officers to have hit the headlines in the US.
It comes as protesters marched through Ferguson, Missouri, to mark the one-year anniversary since the shooting dead of Michael Brown.
Several prominent personalities took to social media to question why Mr Taylor, a second year student at Angelo State University, San Angelo, had been killed.
Tennis star Serena Williams said:
Really??????!!!!!!!!!!? are we all sleeping and this is one gigantic bad nightmare? #ChristianTaylor how many hashtags now?
— Serena Williams (@serenawilliams) August 8, 2015
On his Twitter page, Mr Taylor described himself as a "firm believer in God" and referenced a quote from the Biblical book of Isaiah which states that: "No weapon formed against you shall prosper ... This is the heritage of the servants of the Lord."
American civil rights activist DeRay Mckessen retweeted another of Mr Taylor's tweets in tribute, that said: "I don't wanna die too younggggg."
Mr Taylor's great uncle told the local paper the Fort Worth Star Telegram that he was a talented football player and he couldn't imagine why he would have wanted to burgle a car dealership.
Clyde Fuller told the newspaper: "He was a good kid. I don't see him stealing no car or nothing like that."
Police were called at around 1am on Friday by a security company that had been observing the outside of the dealership.
Police spokesman Sgt Paul Rodriguez told the Star Telegram that when the officers arrived, they discovered that Mr Taylor had crashed a vehicle into the front of the showroom.
He said surveillance footage showed Taylor engaging in "criminal activity", crashing his SUV into the dealership's metal gate, getting out of his vehicle after the crash and damaging a vehicle parked in the forecourt and, later, driving through the showroom glass.
He said: "The officers went and confronted him. There was an altercation. An officer discharged his weapon and struck the suspect."
Sgt Rodriguez added: "As an agency, we take the loss of any human life as serious, but we owe it to our community to conduct a clear and transparent investigation to determine what exactly took place."
At a news conference, Arlington police chief Will Johnson confirmed that a special FBI agent would be helping in the probe - however, he remains confident that the department will investigate the teenager's death fairly.
