SANTA ANA (AP) — A replica handgun was found at the scene where a police officer fatally shot a 17-year-old girl after an encounter as both were driving on a Southern California freeway last week, authorities said Tuesday.

The replica was identical to a Beretta 92 FS handgun, the Orange County District Attorney’s Office said in a news release.

An on-duty Fullerton officer was driving his K-9 dog to a veterinarian in his police SUV on Friday when he saw the teen driving at a high rate of speed, according to the release.

At some point, the two vehicles “made physical contact” and then the shooting occurred, the release said. Prosecutors did not say what prompted the officer to open fire.

The family of Hannah Linn Williams has demanded answers to what they said “appears to be another unjustified shooting of a young person of color.”

In a statement, the family called on the state attorney general to conduct a civil rights investigation.

Witness Renay Arnold said the girl ignored the officer’s orders.

“She brought her arms up with a gun. Now, I don’t know why. I don’t know why. He had his gun out, you can see it clearly. He was yelling commands at her but she didn’t listen,” Arnold told KABC-TV .

It wasn’t immediately clear if the teen was inside her vehicle when the shooting took place, or had stepped outside. She died at a hospital.

A District Attorney investigation will determine whether the police shooting was lawful.