Updated at 1 p.m. ET
An East Pittsburgh, Pa., police officer has been charged with one count of criminal homicide in last week's shooting death of a 17-year-old fleeing a traffic stop that prompted days of angry protests.
Michael Rosfeld, 30, was arrested and charged Wednesday morning, according to court documents. He was released after posting $250,000 bail.
Rosfeld has been on administrative leave since the June 19 shooting. He had reportedly officially been sworn into the job with the East Pittsburgh Police Department just hours before the incident.
Antwon Rose II was shot three times as he ran from the car that police had just pulled over in the Pittsburgh suburb.
"It's an intentional act, and it's done recklessly," Allegheny County District Attorney Stephen Zappala Jr. said at a news conference Wednesday. "There is no justification for it."
Rose was unarmed, according to police, who say an empty gun clip was later found in his pocket.
A witness video of the incident has been viewed about 150,000 times on Facebook; it shows Rose and a second passenger running from police as three shots are heard. Rose is seen collapsing.
Rose was shot in the face, the elbow and the back, according to Zappala.
Of the back wound, Zappala said, "That's the fatal shot," adding the "9 mm slug matches Rosfeld's service weapon."
Police said the Chevrolet Cruze was pulled over because it matched the description of a vehicle involved in a drive-by shooting minutes earlier in nearby North Braddock Borough that left a 22-year-old with a "grazing" wound.
Zappala said a 9 mm weapon as well as a .40-caliber — used in the earlier shooting — was retrieved from under the front seat of the car Rose was riding in. Both weapons were stolen.
And yet, according to Zappala, Rosfeld was never at risk from a weapon.
"He specifically says that he didn't see a weapon," Zappala said. "That's significant."
A police affidavit says video surveillance footage of the North Braddock shooting shows a passenger wearing a dark shirt in the back firing a weapon from an open window. Police do not suspect Rose, who was seated in the front seat, of firing any shots.
The backseat passenger, who also ran with Rose, was later identified as Zaijuan Hester. He was arrested on Monday and charged Wednesday with attempted homicide.
"Antwon Rose didn't do anything in North Braddock other than be in that vehicle," Zappala said.
The driver was detained the day of the shooting and then released without charge after questioning, police said.
"The best we can tell, he is like an Uber driver," Zappala said. "He was very forthcoming."
In the week since Rose died, hundreds of protesters have taken to the streets of the Pittsburgh area demanding action and "Justice4Antwon."
Lee Merritt, who represents the Rose family, said Wednesday that while the family is glad Rosfeld was arrested and charged, action should have been taken sooner.
"When that video first went viral of Antwon Rose being shot in the back three times — at that time, there was no justification; an arrest warrant should have been issued immediately," Merritt said, according to audio released by ABC.
"The family views the homicide charge with guarded optimism," he added. "We believe it's a step in the right direction but we understand that there's gonna be a long road to a conviction and sentencing."
Hundreds of mourners gathered for Rose's funeral service Monday at Pittsburgh's Woodland Hills Intermediate School, reports WESA.
The service program told of his love of basketball, skating and surfing. It described him as a good student.
And it included a poem Rose had written, entitled: "I Am Not What You Think!" It reads in part:
"I see mothers bury their sons, I want my mom to never feel that pain, I am confused and afraid ... I understand people believe I'm just a statistic, I say to them I'm different."
Ahead of Rose's wake on Sunday, his mother, Michelle Kenney, spoke to ABC News about the officer who shot her son.
"He murdered my son in cold blood," Kenney said. "If he has a son, I pray his heart never has to hurt the way mine does."
The Pittsburgh Post-Gazette reports Rosfeld left his last job, at the University of Pittsburgh, after discrepancies were found between his sworn statement and evidence in a December arrest.
The newspaper reports that the East Pittsburgh Police Department hired Rosfeld a few months later in May.
Rosfeld has given a statement to police but has not spoken publicly about the incident.
Of how Rosfeld feels after the fact, "I know that he was remorseful," Zappala said Wednesday.
A preliminary hearing in Rosfeld's case is scheduled for July 6.