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A man has admitted to driving the vehicle from which Jazmine Barnes, 7, was fatally shot in Texas last week, according to a prosecutor at Harris County Probate Court.

Eric Black Jr. told officials he was driving the vehicle while another suspect, identified as Larry W., opened fire from the front seat at the vehicle Jazmine was riding in, the prosecutor said in court.

Black, 20, was arrested Saturday night in Texas and admitted to taking part in the shooting, the Harris County Sheriff's Office said. Officials have filed a capital murder charge against Black after he was identified based on a tip. He was being held without bail.

Jazmine Barnes, 7, was fatally shot in a Walmart parking lot in Harris County, Texas, on Dec. 30, 2018. Family photo

On Sunday, Harris County Sheriff Ed Gonzalez said activist Shaun King provided the tip that led to Black’s arrest.

King, who publicized a $100,000 reward in the case to his 1.1 million Twitter followers, said he had received information from confidential informants about Black and a second man who has not been charged in Jazmine's killing.

Referencing information provided by King, prosecutors said in court documents that Black and the second man, identified as Larry W., did not know they had shot into Jazmine's car until they saw the story on the news later that day.

All evidence gathered so far in the Jazmine Barnes Homicide case supports investigators’ strong belief that she and her family were innocent victims. #JusticeforJazmine #hounews — HCSOTexas (@HCSOTexas) January 6, 2019

At a news conference Sunday, Gonzalez said his office was still verifying information about the second person, whom he did not identify. He said Jazmine's killing appeared to be a case of mistaken identity.

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“The intended target was someone else,” he said, adding that Black and the apparent second man “don’t know the family.”

Authorities had initially identified the suspect in the alleged murder as a bearded white man in his 40s driving a red pickup truck — a description that came from family members who were in the car with Jazmine when she was killed, Gonzalez said.

He said Sunday that this person was probably a witness.

“This just went down very quickly when the gunfire erupted,” he said. “You’re talking about small children — they witnessed something very traumatic.”

The last thing they probably saw was the driver in the red truck, Gonzalez said, adding that he didn’t believe the family was involved in anything “nefarious.”

After the news conference, Jazmine's father, Christopher Cevilla, thanked authorities for tracking down his daughter’s alleged killer.

“I’m hurt, I’m upset,” he told NBC affiliate KPRC. “But at the same time, I’m happy law enforcement did their job.”

Meanwhile, Black admitted to driving what he said was a rental vehicle and told officials the pistol used was at his home, according to the prosecutor.

He gave officials permission to search his property and investigators later recovered a 9 mm pistol consistent with the shell casings recovered from the scene, the prosecutor added.

It was not immediately clear if the other suspect, Larry W., had been arrested.

Jazmine was killed after a gunman fired into the car she was riding in with her mother and siblings at about 6:50 a.m. Dec. 30, officials said. She died from a gunshot wound to the head, according to the prosecutor at Harris County Probate Court.

With no apparent provocation or motive in the shooting, and with an initial description of a suspect as a white man, the killing had raised fears that it could have been racially motivated. Jazmine's mother, who was also wounded, said before the arrest that she believed the shooting was possibly a hate crime.

Earlier Saturday, community members held a rally near the business close to where the shooting took place, calling for justice for the slain girl.T

Jazmine’s mother, LaPorsha Washington, said at the rally that she believed the killer would be caught, and that "there’s too many people out here looking for this man."

The killing prompted gestures of support, and more than $100,000 was raised for a reward in an effort spearheaded by civil rights activist Shaun King.

Basketball great Shaquille O’Neal and a Houston police officer stepped up to pay for the girl’s funeral. Houston Texans star wide receiver DeAndre Hopkins said he would pledge his playoff check to help the family and the effort to find the suspect.