Newly released dash cam video shows a Texas state trooper drawing his stun gun and threatening to “light up” a black woman during a routine traffic stop.

Trooper Brian Encinia pulled over 28-year-old Sandra Bland on July 10 for failing to use her signal when switching lanes. She died in her jail cell three days later, and her cause of death remains in dispute.

The conversation initially turned tense when Encinia told Bland to put out her cigarette, and Bland questioned why she couldn't smoke in her own car.

The dash cam video shows that Bland repeatedly asked why she was being apprehended, while Encinia demanded that she get out of the car.

“I’m going to drag you out of here,” he said when she refused to exit her vehicle.

“You threatening to drag me out of my own car?” Bland asked.

“Get out of the car, I will light you up,” Encinia yelled.

Authorities say that Bland hanged herself with a trash bag in her Waller County Jail cell just three days after she was arrested, and an autopsy report corroborates the claim.

But Bland’s family doesn't believe the police account. The family claims that Bland told them she was injured in the traffic stop.

Texas Lt. Gov. Dan Patrick pledged to “look under every rock for every clue,” saying that it’s “the proper thing to do.”

Encinia, who has been a state trooper for more than a year, is now on administrative leave while authorities investigate.

Watch Casey Stegall's report on the case above. You can see the full 52-minute traffic stop video below. 

Activists have since alleged that the dash cam footage, released by the Texas Department of Public Safety, was edited. The DPS has said it is investigating those claims.

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