Charlotte protesters keep marching

Nearly a week of recurring protests over the police killing of a black man in Charlotte, North Carolina, showed no signs of abating on Sunday after police released videos of the shooting that did not resolve the question of whether the victim had a gun.

Hundreds marched through the center of Charlotte on a fifth night of demonstrations that stretched into Sunday morning, including white and black families protesting police violence.

One sign read "Stop police brutality" and another showed a picture of a bloody handprint with the phrase #AMINEXT, a social media tag about the fear of becoming a victim of police.

For the first time in three nights, police enforced a curfew, saying they would arrest violators.

A crowd gathered outside police headquarters dispersed without any violence shortly after midnight.

The streets were quiet on Sunday morning, but city officials were preparing for extra security at a National Football League game between the Carolina Panthers and the Minnesota Vikings on Sunday afternoon.

Charlotte-Mecklenburg Police Chief Kerr Putney said his department expects to "expend significant public safety resources" during the game at Bank of America Stadium, which can host more than 70,000 people.

Police released two videos on Saturday showing the fatal shooting on Tuesday of Keith Scott, 43. The controversial death has made Charlotte, North Carolina´s largest city and a financial centre, the latest flashpoint in two years of tense protests over US police killings of black men, most of them unarmed.

Putney acknowledged that the videos themselves were "insufficient" to prove Scott held a gun but said other evidence completed the picture.

"There is no definitive visual evidence that he had a gun in his hand," Putney said.

"But what we do see is compelling evidence that, when you put all the pieces together, supports that.

"Police said officers trying to serve an arrest warrant for a different person caught site of Scott with marijuana and a gun, sitting in a car in a parking lot. "They look in the car and they see the marijuana, they don´t act. They see the gun and they think they need to," Putney said.

Both Scott´s family and protesters have disputed the police statements that Scott was carrying a gun.