Video footage taken from the back of an ambulance does not appear to show conclusively what happened in the fatal shooting of an unarmed black man by a Minneapolis police officer a week ago, Minnesota Governor Mark Dayton said on Monday.

The shooting of Jamar Clark, 24, on Nov. 15 sparked more than a week of protests amid questions over whether he was handcuffed at the time and demands from protesters that authorities release videos of the incident.

Police have denied that Clark, who died the next day from a gunshot wound to the head, was handcuffed when he was shot. The officers involved have been identified.

"I have seen the tape," Dayton told a news conference. "It doesn't show anything that would provide any confirmation to one point of view or another."

As governor, Dayton has direct authority over the Minnesota Bureau of Criminal Apprehension, which is investigating the shooting along with the FBI.

Federal authorities investigating whether Clark's civil rights were violated have said release of videos and other evidence would be detrimental.

Dayton said the camera looked out the back door of the ambulance with the purpose of recording what would occur in the back of the vehicle.

"It is just a very brief fragment where Mr. Clark and one of the officers encounter each other and then they disappear from sight," Dayton said.

Dayton said there was nothing more of substance in the video until, it would appear, after the shot was fired, when one officer comes back into view.

Authorities have said there was no video of the shooting from police dashboard or body cameras, but investigators are reviewing video from business and security cameras in the area, as well as witnesses' cell phones.

The shooting comes at a time of heightened debate in the United States over police use of lethal force, especially against black people. Over the past year, protests against killings of unarmed black men and women - some videotaped with phones or police cameras - have rocked a number of cities.

The NAACP Minneapolis said in a statement that Dayton's remarks reinforced the public's need to see the videotape for themselves.

Dayton has said he has urged that tapes be provided to Clark's family and released publicly when they would not jeopardize a U.S. investigation.

Clark's funeral is scheduled for Wednesday.

Although protests have been largely peaceful, police have used pepper spray and fired rubber marking bullets at least twice when demonstrations became heated.

Several people were shot and wounded late on Monday about a block from the precinct where demonstrators have remained for over a week. Police said they were looking for suspects.

A police union representative has said Clark grabbed one officer's gun, although the weapon remained in its holster