US police have identified a 19-year-old as a suspect in the shooting of about 20 people during a Mother's Day parade in New Orleans, saying several people had identified him as the gunman captured on CCTV.
Superintendent Ronal Serpas said officers were looking for Akein Scott, of New Orleans. He said it was too early to say whether he was the only gunman.
"We would like to remind the community and Akein Scott that the time has come for him to turn himself in," Mr Serpas said at a news conference outside police headquarters.
A photo of Scott hung from a podium in front of the police chief. "We know more about you than you think we know," he added.
The mass shooting showed again how far the city has to go to shake a persistent culture of violence which belies the city's festive image. Mr Serpas said: "The people today chose to be on the side of the young innocent children who were shot and not on the side of a coward who shot into the crowd."
The superintendent said police special weapons team members and US marshals served a search warrant at one location looking for Scott, but did not find him.
Video released on Monday shows a crowd gathered for a boisterous second-line parade on Sunday suddenly scattering in all directions, with some falling to the ground. They appear to be running from a man in a white T-shirt and dark trousers who turns and runs out of the picture.
Police were working to determine whether there was more than one gunman, though they initially said three people were spotted fleeing from the scene.
Officers said in a news release that Scott has previously been arrested for illegal carrying of a weapon, illegal possession of a stolen firearm, resisting an officer, contraband to jail, illegal carrying of a weapon while in possession of a controlled dangerous substance and possession of heroin. It was not clear whether he had been convicted on any of those charges.
Three gunshot victims remain in a critical condition, though their injuries are not thought to be life-threatening. Most of the wounded have been released from hospital.