The wounded in Sunday afternoon's shooting in the largest city and metropolitan area in the state of Louisiana, governed by Indian-American Bobby Jindal, included 10 men and seven women as well as a boy and a girl, both 10.
Local Nola.com citing police said both the 10-year-old victims had graze wounds to the body and were in good condition. A man and a woman were reported to be in surgery Sunday evening.
Immediately after the shooting on Frenchmen Street police reported seeing three suspects running from the scene.
Police Superintendent Ronal Serpas said the three gunmen likely worked together, and at least two different weapons were used. One of the suspects is described as a man between 18 and 22 years old with short hair and wearing a white shirt and blue jeans, Serpas said.
Many of the victims were grazed, some by bullets that ricocheted. "At this point, there are no fatalities, and most of the wounds are not life-threatening," Nola.com cited spokesperson Remi Braden as saying in an email.
"But all medical conditions are not known at this time as victims were rushed to nearby hospitals," Braden said.
"Detectives are conducting interviews, retrieving any surveillance video in the area and, of course, collecting all evidence. This is an extremely unusual occurrence, and we're confident that we will make swift arrests."
Dr Jeff Elder, director of New Orleans Emergency Medical Services (EMS), said that three patients brought in were in critical condition and went straight to operating rooms. The rest, he said, were in good to serious condition and were admitted to the emergency room.
There were about 300 to 400 people participating in the Mother's Day parade, about 200 people apparently were in the area at the time of the shooting, Serpas said.
The New Orleans coroner said no fatalities have been reported from the shooting.