Prosecutors seek to charge teen as adult in hit-and-run death of retired police chief on bike

Las Vegas prosecutors are seeking to charge the teen driver accused of killing a retired police chief on a bike in a hit-and-run last month, as an adult.

A 17-year-old male driver has been in custody since the Aug. 14 crash that killed 64-year-old Andreas Probst as he was biking in the area of Tenaya Way and Centennial Parkway, the Las Vegas Metropolitan Police Department said.

At first, the teenager, found in a stolen 2016 Hyundai, was charged in connection with the hit and run. Open murder charges were added later after police found social media video of the collision, which led them to determine the crash was “an intentional act.”

"The individuals pulled directly behind Probst and ran him over, as they fled the scene and laughed," police said in a statement.

The driver has not been identified as he is a minor.

On Monday, the Clark County District Attorney's Office said they are taking the case "seriously."

"One of the perpetrators, a juvenile, is currently in custody and being held pursuant to charges that have been filed in the juvenile system. Additional charges may be forthcoming," the statement said. "The District Attorney’s Office is seeking certification to adult status of the juvenile perpetrator."

Police and the DA's office also said Monday they are “actively working” to identify the passenger in the suspect vehicle.

"I am confident that justice will be served in this matter once the investigation is complete and the appropriate charges have been filed,” Clark County District Attorney Steve Wolfson said.

On Tuesday, Las Vegas police announced they identified the passenger and arrested him. The minor, who was not identified, will be booked into the Clark County Juvenile Hall on a charge of open murder, police said.

Detectives were reviewing other cases, police said, and have determined that "these individuals were also involved in an additional hit-and-run of a bicyclist prior to killing Probst."

Police haven't identified the video that led to the open murder charges, but over the weekend, footage circulated on social media showing two people in a car laughing as they crashed into a bicyclist.

The clip, taken from the phone of a passenger in the vehicle, shows the car speeding and approaching a bicyclist in a red shirt cycling on the right side of the road.

As they approach the bicyclist, one is heard saying “yeah yeah yeah hit his a--.” Mere seconds later, the car hits the back of the bicycle and the man on it flies backward, slams onto the hood of the car and hurtles onto the pavement.

The teens are heard shouting as they drive off with one exclaiming the man was “knocked out.”

Police would not confirm to NBC News if that was the video they reviewed.

Probst, the former chief of the Bell, California, police department, had been biking around 6 a.m. when he was hit. He was found with life-threatening injuries and pronounced dead at a hospital.

Probst’s family remembered him as a “ray of sunshine.” He had spent 35 years working in law enforcement before retiring from police work in 2009 and moving into a remote job in global security, The Las Vegas Review-Journal reported.

This article was originally published on NBCNews.com