A large crowd of people were gathered at the scene before the shooting occurred, police said.
They then fled the chaotic scene on foot, Harrison said.
New Orleans Police Department Superintendent Michael Harrison described the events leading up to Saturday night's shooting during a press conference later that night. Five men and two women were transported to local hospitals, one of which police described in critical condition and is now in surgery.
Harrison said one underwent surgery and was in critical condition.
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A media report claimed that Syria was in the middle of an operation targeting terrorist groups when the jet was shot down. We will not accept any such penetration of, or spillover into, our territory, neither on the ground nor in the air.
Harrison told reporters that the suspects were believed to be wearing hooded sweatshirts, but that's the only description available.
"A lot of people were out here tonight", he said. "We need them to know that they can trust us and come to us".
Another man, Lawrence Russo, heard the gunfire from inside a nearby Exxon gas station.
Near the site of the shooting, beyond the police tape, people could be seen crying and hugging one another in comfort.
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The three deceased were described as two men and one woman.
In a statement released late on Saturday, New Orleans' mayor, LaToya Cantrell, said she would "dedicate every resource necessary to ending this horror and seeing justice done".
In October 2011, the younger brother of John Matthews, who owned Jazz Daiquiris at the time, was gunned down three days after Hankton was given a life sentence in the 2008 shooting.
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