HEMPSTEAD, Texas — Police dashcam video shows a Texas state trooper trying to drag a black motorist from her car after a minor traffic infraction, then drawing his stun gun and threatening her for refusing to follow his orders.

The video shows the roadside encounter swiftly escalating into a shouting confrontation, with the officer holding a stun gun and warning 28-year-old Sandra Bland, “I will light you up,” for refusing to get out of her vehicle.

Three days later, Bland was found dead in her jail cell. Authorities say she hanged herself with a black plastic garbage bag — a contention her family and supporters dispute.

The video posted online Tuesday by the Texas Department of Public Safety shows the trooper, who is white, stopping Bland for failing to signal a lane change. After he hands her a written warning, the trooper remarks that Bland seems irritated. The Illinois woman replies that she is irritated because she had changed lanes to make way for the trooper’s car.

The conversation quickly turns hostile when the officer asks Bland to put out her cigarette and she asks why she can’t smoke in her own car. The trooper then orders Bland to get out of the vehicle. She refuses, and he tells her she is under arrest.

Further refusals to get out bring a threat from the trooper to drag her out. He then pulls out a stun gun and makes the threat about lighting Bland up.

When she finally steps out of the vehicle, the trooper orders her to the side of the road. There, the confrontation continues off-camera, but it is still audible. The two keep yelling at each other as the officer tries to put Bland in handcuffs and waits for other troopers to arrive.

Still off camera, Bland can be heard protesting her arrest, repeatedly using expletives and calling the officer a “pussy.” She screams that he’s about to break her wrists and complains that he knocked her head into the ground.