The family of a 17-year-old girl fatally shot by a Fullerton police officer on the 91 Freeway in Anaheim will publicly demand Tuesday that Gov. Gavin Newsom order a civil rights investigation by Attorney General Xavier Becerra.

In a statement issued Tuesday morning, the family of Hannah Williams also called on the Rev. Al Sharpton to intervene in the case, and urged the city to suspend the officer involved in the shooting.

“We want Rev. Sharpton to shine a light on what happened here in Anaheim,” said Benson Williams, the girl’s father. “We want to know why police felt the need to shoot and kill a 17-year-old unarmed teen girl.”

Relatives are expected to be joined at a news conference Tuesday afternoon by the Rev. Jarrett Maupin of Sharpton’s National Action Network, along with NAACP officials. The news conference will be held at 1 p.m. outside Anaheim City Hall, 200 S. Anaheim Blvd.

“The public wants to know what happened and whether or not the officers involved followed all policies and procedures. We have doubts,” according to the family’s statement.

The family also announced plans to “have an independent autopsy conducted, fearing police will delay in releasing official autopsy results and continue to withhold information about the nature of the shooting from the public. The Williams Family wants to set the standards for transparency in this case,” Maupin said.

The Williams family said it had established a GoFundMe account to assist with funeral expenses. Details will be announced at the news conference.

According to Anaheim police, a Fullerton police K-9 officer radioed around 7 p.m. Friday that he had been involved in a shooting on the freeway.

“A female suspect was struck by gunfire and was transported to a local hospital where she later died,” according to an Anaheim police statement.

No officers were injured during the shooting, police tweeted.

According to Anaheim police, an “item appearing to be a handgun was recovered at the scene.” In a Twitter post, the department said the item would be tested to determine whether “it was real, functional, loaded.” No test results have been announced.

Maupin, who is acting as a Thomas family spokesman, said Hannah Williams did not have a gun on her when she was shot. The teen had a cellphone, he said.

“We know she was unarmed,” Maupin said.

Events that led to the shooting were still unclear, although the Fullerton officer’s police car had apparently been struck by another vehicle moments before the shooting.

Witness Renay Arnold told NBC4 she saw Williams standing on the freeway outside of her vehicle and approaching the officer despite multiple commands by the officer that she stop.

“She looked angry and she was walking towards him, the officer. … She raised both arms with a 9mm gun and he had to shoot her. He shot her. Three times. Bang bang bang.”

Maupin said Williams, who worked as a lifeguard, spent Friday with her family at their home in Anaheim before leaving that evening. He said the accident involving the Fullerton police squad car “was very minor.”

Williams moved to the area less than a year ago with her family from Phoenix.

Anaheim police said more information may be released this week after potential witnesses are interviewed.

“The freeway was packed and all potential witnesses need to be interviewed first. We cannot risk influencing someone’s statement, by releasing details prematurely,” the department tweeted. The Fullerton Police Department has not commented on the shooting, other than confirming one of its officers was involved.

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