The black man charged in the murder of seven-year-old Jazmine Barnes allegedly told authorities those involved shot at the wrong vehicle by mistake as it emerges civil rights activist Shaun King passed on the tip that led to his capture.

Eric Black Jr, 20, was arrested and charged with capital murder on Sunday after the little girl was shot dead near a Walmart parking lot in Houston on December 30.

Black told investigators he was driving the vehicle from which a passenger opened fire when Jazmine was killed.

Another man, Larry Woodruffe, 24, was the second suspect to be taken into custody.

The Barnes family's lawyer, Lee Merritt, released a copy of Woodruffe's mugshot on Sunday and said he is 'believed to be the shooter'.

Harris County Sheriff Ed Gonzalez would not confirm the second suspect's name because he has not been formally charged.

Jazmine's family had told authorities that the gunman was a white man driving a red pickup truck, which stirred fears among community activists that race played a role in the attack.

Gonzalez said Black had admitted to driving a dark-colored SUV that he had rented at the time of the shooting.

Authorities believe the red truck and possible white driver was in the vicinity at the time but fled during the gunfire.

Eric Black Jr, 20, (left) has been charged with capital murder after seven-year-old Jazmine Barnes who was gunned down in a Walmart parking lot in Houston, Texas on December 30. Another man, Larry Woodruffe, 24, (right) was the second suspect to be arrested in connection with the shooting

Jazmine was in the family's car with her mother and three siblings when a red pickup truck pulled up next to them and someone started firing inside the vehicle

Jazmine was in the family's car with her mother and three siblings when a gunman started firing at them.

Police initially described the suspect as a bearded white man in his 40s based on the descriptions from various witnesses and victims.

Police had initially described the suspect as a bearded white male in his 40s based on witness descriptions. Following the arrest of two black men, it is now believed the man seen fleeing the scene may have been an innocent, frightened bystander

They released a police sketch showing a white man and Jazmine's mother, LaPorsha Washington, said she believed the shooting was racially motivated.

However, both men taken into custody in connection with the little girl's murder are black.

Police have since revealed they believe the shooting was a case of 'mistaken identity'.

Black was stopped by police on January 5 for failing to signal before changing lanes and officers subsequently found marijuana in his car.

When he faced court for the signal and drug violations, it was revealed authorities had received an anonymous tip that said people with the initials 'EB' and 'LW' were responsible for the shooting, ABC News reports.

Sheriff Gonzalez revealed on Sunday that Shaun King was the person who phoned in the tip that he had received with names of the alleged shooters.

Black later allegedly told police that he owned a pistol, which is said to have matched the casings found at the murder scene.

Police said early Sunday that Black was arrested without incident after receiving a tip and later admitting to the shooting

Sheriff Ed Gonzalez revealed on Sunday that civil rights activist Shaun King (above) was the person who phoned in the tip that he had received with names of the alleged shooters

Investigators do not think Jazmine or her family were the intended targets of the shooting.

'Investigators are continuing to pursue evidence that could possibly lead to other suspects being charged in this case,' a statement read.

'Jazmine's mother was driving Jazmine and her three sisters southbound on the East Sam Houston Parkway feeder road near Wallisville Road at approximately 6:50 a.m. when they were fired upon by someone in another vehicle.

'At this time, investigators do not believe Jazmine's family was the intended target of the shooting, and that they were possibly shot as a result of mistaken identity.'

'I am grateful to our dedicated investigators, the partner law enforcement agencies that provided vital assistance, and tipsters from across the nation who pulled together to support our work to get justice for Jazmine,' Sheriff Ed Gonzalez said. 'Our work is not finished, but I believe the people of Harris County can take comfort in knowing we have made great progress.'

It comes as hundreds of people gathered at a rally on Saturday holding signs reading 'Justice for Jazmine.'

Organizers of the rally also led the crowd in chants that repeated the phrases, 'What do we want? Justice. Who do we want it for? Jazmine.'

Jazmine's family had said they believe her death was racially motivated.

In an emotional speech, Jazmine's aunt, Sharonica Watt, asked her niece's killer why he took the little girl's life.

'We're asking you to turn yourself in right now, in the name of Jesus. We're asking you to give justice to me and my family,' Watt yelled in between tears.

Jazmine was killed when a man in a red pickup truck pulled up next to the family car and opened fire for no apparent reason

At least one suspect is reportedly in custody in connection with the seven-year-old's murder

Jazmine died at the scene and her mother, LaPorsha Washington, suffered a gunshot wound to the arm.

Jazmine's father, Christopher Cevilla, said his daughter was a loving and caring girl who was 'very smart in school.'

The Sheldon Independent School District said in a statement that Jazmine was a second-grader at Monahan Elementary in Houston.

The district said additional counselors will be at the school when students return on Tuesday. The district asked parents to tell their children about Jazmine's death.

Her funeral is being paid for by retired NBA player Shaquille O'Neal and veteran Houston police officer Kenneth Miles.

Texans star DeAndre Hopkins donated his $29K check from Saturday's game to support her family.

LaPorsha Washington, center, the mother of seven-year-old daughter Jazmine Barnes, speaks to the crowd during a community rally

The rally was held in the parking lot of a Walmart near where the shooting happened

People attend a community rally for seven-year-old Jazmine Barnes on Saturday in Houston