(CNN) -

On August 16, Oklahoma twins Terence and Tiffany Crutcher celebrated their 40th birthday. Terence, a God-loving father who sang at church every week, had enrolled at a community college in Tulsa where he hoped to earn a degree.

"I'm going to show you," Terence recently texted his sister. "I'm going to make you all proud."

He never was able to follow through on that promise.

On the night of September 16, exactly one month later, Crutcher's SUV broke down, according to his family.

After police responded to a 911 call about the vehicle, the 40-year-old black man found himself raising his hands high above his head. Moments later, Officer Betty Shelby fatally shot Crutcher. He was later found to be unarmed, according to authorities.

Now, as multiple investigations are underway, Crutcher's sister has demanded prosecutors immediately press charges against Shelby. CNN's efforts to reach out to an attorney for Shelby have been unsuccessful.

'Difficult to watch'

Three days after Crutcher's death, the Tulsa Police Department Monday released 911 audio, dashcam videos, and a police helicopter video of the incident. Chuck Jordan, Tulsa's chief of police, described the footage as "very disturbing and difficult to watch."

Sometime after 7:30 p.m. September 16, dispatchers received two 911 calls. The first call came from a woman who said an abandoned vehicle was blocking a road.

"Somebody left their vehicle running in the middle of the street with their doors wide open," the caller said. "The doors are open, the vehicle is still running. It's an SUV. It's in the middle of the street, it's blocking traffic."

The woman also told the 911 operator that "the guy was running from [the vehicle]" after explaining to her it was going to "blow up."

Shelby was headed to a domestic violence call when she arrived first at the scene of Crutcher's stalled vehicle. Shelby told the dispatcher that "she's not having cooperation" from Crutcher, according to Chief Jordan at a Monday news conference. The police chief declined to offer more information regarding the lack of cooperation Shelby faced.

When Shelby arrived, Crutcher was on the side of the road, away from his vehicle. He then approached Shelby, police said.

'Shots fired'

By the time Crutcher raised his hands, Tulsa Police officers were also flying above the scene in a helicopter, capturing the incident from an on-board camera. Footage from multiple police cameras show Crutcher walking toward his SUV in the middle of the road, hands raised, followed closely by Shelby and three other officers. They surround Crutcher, who continued to walk back to his car, where he appeared to place his hands toward the vehicle.

Circling above the scene, one police officer in the helicopter can be heard referring to Crutcher as a "bad dude," according to audio from police footage.

Jeanne MacKenzie, Tulsa Police public information officer, said that the responding officers on the ground thought Crutcher had reached his hands into the driver's side window of the vehicle.

Moments later, as Crutcher stands beside his car, the video shows him fall to the ground

"I think he may have just been Tasered," an officer says over the radio.

"Shots fired!" a female officer says.

In the video, Crutcher lies in the middle of the street, motionless, soon to be dead.

'There was no gun'

At a news conference Monday, Jordan struck a candid tone about the officer-involved shooting that left Crutcher dead.

"I'm going to tell you right here now: There was no gun on the suspect or in the suspect's vehicle," Jordan said.

He also confirmed that Shelby had fired one shot and Officer Tyler Turnbough had deployed his Taser.