DENVER — Police told teens several times to get out of a stolen car before opening fire and killing the 17-year-old girl behind the wheel as she drove at one of the officers, Denver’s police chief said.

The officer was between the car and a brick wall and felt threatened as he and a colleague fired, killing Jessica Hernandez, Chief Robert White, citing preliminary information, told The Denver Post in a story Thursday.

White said he cannot judge whether the officers acted appropriately until criminal and internal investigations are completed.

“Like I said the morning of the incident, there are a lot of unanswered questions,” he told the newspaper.

A passenger in the car, who spoke on condition of anonymity because of safety concerns, has disputed the official account of the shooting, saying officers came up to the car from behind and fired four times into the driver’s side window.

Hernandez’s mother said Wednesday she wants a second, independent autopsy because she doesn’t trust the official investigation into the

death of her daughter.

“I want to know, how did this happen,” Laura Sonya Rosales Hernandez, speaking in Spanish, told The Associated Press inside the trailer home where her daughter lived with five siblings. “I want to know everything.”

The shooting occurred amid a national debate about officers’ use of force fueled by killings in Ferguson, Missouri, and New York City.

It was the fourth time in seven months that a Denver officer shot at a vehicle after perceiving it as a threat. One resulted in the death of a 21-year-old man.

The U.S. Supreme Court has said that officers may not use deadly force to stop a fleeing suspect unless the person is believed to pose significant physical harm. Still, policies vary among agencies, and some departments have banned or discouraged the practice.

The Albuquerque Police Department, for example, ordered officers in June to stop shooting at moving vehicles after a U.S. Justice Department report found a pattern of excessive force.

In Denver, the Police Department and independent monitor Nicholas Mitchell separately are looking at how national standards compare to Denver’s policy, which allows officers to fire at moving cars if they have no other reasonable way to prevent death or serious injury.

Denver’s policy says, “An officer threatened by an oncoming vehicle shall, if feasible, move out of the way rather than discharging a firearm.”

Experts say shooting and disabling a driver can send a car out of control.

“If you were to shoot at the driver, you would have an unguided missile, basically,” said Chuck Wexler, executive director of the Police Executive Research Forum, which suggests departments forbid officers from shooting at moving vehicles unless there is another deadly threat involved, such as a weapon.

Police identified the officers in the Hernandez shooting as Daniel Greene, a 16-year-veteran, and Gabriel Jordan, a nine-year veteran. Hours after their names were released Wednesday, a group gathered outside the police station calling for justice.

Jordan suffered a fractured leg, department spokesman Sonny Jackson said, declining to comment further about details of the case.

Hernandez’s mother said her daughter made a mistake by “grabbing” a car that did not belong to her but didn’t deserve to pay with her life.

“How much do they need to investigate?” she asked. “It’s all done. They did it. They killed her. All I want is justice.”

The passenger in the car, who spoke on the condition of anonymity because of safety concerns, said Hernandez lost control of the vehicle because she was unconscious after being shot.