Police in Tulsa, Oklahoma released video on Monday showing an officer fatally shooting an unarmed black man who had his hands in the air, and the U.S Justice Department said it was looking into the incident as a possible civil rights violation.

Officer Betty Shelby shot Terence Crutcher, 40, whose sport utility vehicle broke down on Friday, police said. Crutcher was pronounced dead at an area hospital.

The case is the latest in a string of shootings of unarmed black men by U.S. police that have raised questions of racial bias in police forces.

"We will achieve justice in this case," Tulsa Police Chief Chuck Jordan told a news conference adding the release of video was done as a matter of transparency.

Jordan said he found the videos "very disturbing, very difficult to watch."

"Without a doubt we believe this was an unjustified shooting that should not have happened," family attorney Damario Solomon-Simmons said at a separate news conference, adding that they are seeking criminal charges.

In one video shot from a police helicopter, Crutcher is seen with his hands in the air, followed by an officer with a drawn weapon. He then puts his hands on the vehicle.

One of the officers in audio from the helicopter says Crutcher is not following instruction. Another says "that looks like a bad dude too, could be on something." Crutcher then drops to the ground and a female officer can be heard on police radio saying: "shots fired."

Crutcher is then seen on his back with what appears to be blood oozing from his torso.

In a police dashcam video, one officer with a weapon drawn trails Crutcher as he walks to the vehicle. A pop is heard and he falls a few seconds later.

"We think he may have just been Tasered," a man's voice is heard on a police radio. "Shots fired," a woman's voice then says.

One officer, identified as Tyler Turnbough, used his Taser on Crutcher, Tulsa police said, adding Shelby, fired her gun at the man. She has been placed on administrative leave, they said.

Shelby was not immediately available for comment.

Crutcher did not have a weapon on him or in his vehicle, police said, providing few details of the incident. They said Crutcher refused to follow officers' commands in the minutes before he was shot.

The U.S. Department of Justice has launched a separate civil rights inquiry into the officers' use of force, U.S. Attorney Danny Williams with the Northern District of Oklahoma said on Monday.