Police spokeswoman Remi Braden said in an email that many of the 17 victims were grazed and most of the wounds weren't life-threatening. No deaths were reported.
Police superintendent Ronal Serpas told reporters that a 10-year-old girl grazed by a bullet was among those wounded in the shooting. She was in a good condition. He said three or four people were in surgery, but he didn't have their conditions.
Officers were interspersed among the hundreds of marchers – a routine move during what is known as second-line parades, loose processions in which people dance down the street, often following behind a brass band.