(CNN) A jury found former East Pittsburgh Police Officer Michael Rosfeld not guilty of all charges Friday night in the fatal shooting of 17-year-old Antwon Rose II, Allegheny County District Attorney spokesman Mike Manko said.

Demonstrators gathered outside the courthouse as soon as the verdict came in. The June 19 shooting sparked protests as crowds questioned the police department's use of deadly force against an unarmed youth.

#BREAKING NEWS: Streets in downtown #Pittsburgh being blocked due to Antwon Rose protesters. Former officer Michael Rosfeld found not guilty of killing Rose. https://t.co/p06bSfsjXa pic.twitter.com/MgId4Ordct

"While the family of Antwon Rose is devastated that former officer Michael Rosfeld was acquitted today, they are grateful for the support of the community and from many around the country," said S. Lee Merritt, an attorney for the Rose family, in a statement.

Rose was shot three times when he ran during a traffic stop. A witness to the shooting captured it on video that was posted on Facebook.

Prosecutor Dan Fitzsimmons told jurors in opening statements that video showed Rose running from Rosfeld and "causing him no danger whatsoever." Rosfeld and his defense lawyer said the officer felt threatened and thought he'd seen what might have been a gun.

Rosfeld, 30, faced one criminal homicide charge. The jury was instructed to consider first-degree murder, third-degree murder, voluntary manslaughter or involuntary manslaughter. If convicted, he could have been sentenced to life in prison.

After hearing three-and-half days of testimony, the jury deliberated four hours and found him not guilty on all counts.

The shooting raised racial tensions. Rosfeld is white and Rose was black.

17-year-old Antwon Rose

Merritt, the attorney for Rose's family, told reporters outside the Allegheny County Courthouse that the verdict as "very disappointing for this family."

"Antwon Rose was shot in his back, which killed him. He was unarmed, and he did not pose a threat to the officer or to the community, and the verdict today says that is OK, that is acceptable behavior from a police officer."

Allegheny County District Attorney Stephen Zappala Jr. released a statement on the verdict.

"While I respectfully disagree with their verdict, it is the people of this commonwealth who decide guilty or not guilty and they have spoken to this matter," the statement said. "In the interest of justice, we must continue to do our job of bringing charges in situations where charges are appropriate, regardless of the role an individual holds in the community."

'I'm not going to wait to be attacked'

In testimony Thursday, Rosfeld said he initially pulled over the gold Chevy Cruze because it matched the description of a car involved in a drive-by shooting 20 minutes earlier. The car with a shattered rear windshield was riddled with bullet holes when Rosfeld called in a felony traffic stop.

On the witness stand, he demonstrated the hand motions he said he perceived as a threat to his life seconds before he fired three shots toward Rose and the other passenger trying to flee.

Rose family attorney, S. Lee Merritt, left, and Michelle Kenney, mother of Antwon Rose II, address reporters Friday.

During the direct questioning by his own defense attorney Patrick Thomassey, Rosfeld testified that he was following procedure for a felony stop and communicated that over the police radio, signaling a raised-risk situation to other officers.

"I'm not going to wait to be attacked," Rosfeld said on the stand when pressed by prosecutor Dan Fitzsimmons on why he didn't wait in his police vehicle until other officers arrived on the scene.

Rosfeld said he saw both Rose and the other passenger, now known to be Zaijuan Hester, then 17, move from the car at the same time. He acknowledged that he couldn't differentiate between the two to say which one was pointing what he thought was a handgun at him, so he fired his gun in the general direction of both.

#BREAKING: Large crowd gathering outside of Allegheny County Courthouse after former East Pittsburgh Police officer Michael Rosfeld found NOT GUILTY of shooting and killing Antwon Rose. https://t.co/Urln5l8RnX



WATCH LIVE: https://t.co/B3tu8Z7pe4 pic.twitter.com/jwEoJnpsda — KDKA (@KDKA) March 23, 2019

"I meant to fire until the threat against me had been ended, whether it be if I missed and he surrenders, stops, gets on the ground. I just wanted to end the threat to me," Rosfeld responded when asked by the prosecutor whether he meant to kill.

Fitzsimmons also pressed Rosfeld on what exactly he knew about the drive-by shooting in the moments leading up to when he shot Rose.

Rosfeld testified that he knew from radio dispatch communication that there had been between 10 and 12 shots fired during the drive-by shooting that happened just about a mile and half from where he encountered the suspect vehicle and Rose, which Rosfeld said signaled to him that there may have been more than one armed suspect in the car.

Rosfeld initially told police his intention had been to get all three occupants on the ground as he awaited backup, according to the original criminal complaint.

Witnesses say Rosfeld was distraught

After ordering the driver onto the ground, he said, the front seat passenger, Rose, exited the vehicle and "turned his hand toward Officer Rosfeld and he, Officer Rosfeld, saw something dark that he perceived as a gun."

Rosfeld has been criticized for an inconsistency in his tellings of the incident, because when asked again to recount the events, Rosfeld "told the detectives that he did not see a gun when the passenger emerged and ran. When confronted with this inconsistency, Rosfeld stated he saw something in the passenger's hand but was not sure what it was," the complaint said.

Though unbeknownst to Rosfeld when he fatally shot Rose, police later found two stolen guns in the car, traces of gun residue on Antwon Rose's hand and the empty clip of a handgun in his pants pocket, according to court records.

Several witnesses during the trial testified that Rosfeld was distraught and emotional after realizing he fatally shot Rose.

A witness, Pat Shattuck, who was at the East Pittsburgh Borough Senior Citizen Center at the time of the incident testified Wednesday that he heard Rosfeld through sobs say, "Why did he do that? Why did he do that? Why did he take that out of his pocket?"

John Leach, a resident of the neighborhood where Rose was shot, testified that after the shots were fired he saw Rosfeld standing on the sidewalk "panicking," according to CNN affiliate WTAE. Leach said the officer kept repeating the same thing over and over: "I don't know why I shot him. I don't know why I fired."

Rosfeld testified that he'd been sworn in in that same building just nearly an hour before the incident. He'd been working on the job for about two weeks before that and had been a police officer in other jurisdictions since 2011, Rosfeld said.

Testimony started Thursday. The defense rested Friday morning. The only other defense witness was a use-of-force expert, Clifford Jobe.

Judge Alexander Bicket also ruled Friday morning in favor of the defense's request to lift the gag order that had been in place since September. The jury has been selected from Dauphin County, which is about 200 miles from Pittsburgh, after a ruling that the publicity around the case had affected the jury pool in Allegheny County. The trial is taking place in Pittsburgh with the jurors from Dauphin County.

Merritt said the family will continue to fight this ruling.

"It will have to be challenged, in the Supreme Court of Pennsylvania. It will have to continue to be challenged on a federal level," he said.

Clarification: A previous version of this story mischaracterized the charge levied against Officer Michael Rosfeld. He only faced one charge of criminal homicide.