Story highlights

NEW: Crimestoppers raises reward to $5,000 after dearth of tips in investigation

300 to 500 people had gathered at park for an impromptu music video filming

Officers were already in route to break up the gathering, when a firefight broke out

CNN  — 

A shooting in a New Orleans park left 17 people injured, and police say they know there are “hundreds of witnesses” who have yet to come forward with what they know.

Several hundred people – estimates range between 300 and 500 – had gathered at Bunny Friend Playground for an impromptu music video filming late Sunday when two groups began firing on each other, the New Orleans Police Department said in a statement.

“Witnesses told police that both groups left the park on foot immediately after the shooting,” police said. Officers were already in route to break up the gathering, when the shooting broke out. … They were about a block away when they heard gunshots.”

Ten women and seven men – 11 of them younger than 21 – were injured and received treatment at area hospitals, Mayor Mitch Landrieu said in a news conference. Eight of them were transported to the University Medical Center trauma center.

Landrieu said he and Police Superintendent Michael Harrison visited victims in the hospital and were particularly impressed with a 10-year-old who told them he wanted to join the Army when he grew up.

Landrieu said he was proud to see the youngster, suffering from a bullet wound, wanting to serve his country when other young people seem intent on tearing it apart.

“He was really being brave and courageous,” the mayor said.

Landrieu likened the incident to domestic terrorism. Harrison questioned how two groups of people could open fire on each other – with what appears to be automatic weapons, judging from the shell casings – with hundreds of people in between them.

“This is absolutely senseless. We’re not going to stand for it. We’ll never stand for it,” Harrison said.

There are plenty of witnesses – hundreds of them – that saw what happened, and Landrieu and Harrison shared their hunch that many of those witnesses may have captured the violence on video. A Crimestoppers representative said she was so disappointed by the dearth of calls coming in on the case that her agency had upped its reward to $5,000.

“If you want to take back your community, you have to help us,” Landrieu said. “I need everyone to step up if you want to make this city a city of peace.”

Detectives are searching for surveillance video of the shooting and suspects.