Watch: People panic, run for cover after mass shooting in US leaves 8 people injured, 1 critical

Police in Florida said eight people were shot on Monday during a Martin Luther King Jr. Day event, with one of the victims listed in critical condition.

The St Lucie County Sheriff’s Office confirmed that all the victims in the early evening shooting in Fort Pierce were adults, a local television station reported.

The shooting occurred at Ilous Ellis Park at 5.20pm (US time) during an MLK Car Show and Family Fun Day, which the sheriff's office said was attended by more than 1,000 people, local media reported.

“It was mass chaos, as you can imagine, when shots rang out," Hester said. “There were a thousand-plus people here at the event, and as the shots rang out, people were just running in all directions."

Video obtained by the TV station showed people ducking, running, and hiding behind cars, including a woman running to safety while holding a baby.

The sheriff’s office said two deputies at the event responded immediately and aided victims, WPBF-TV reported.

“Multiple people were shot, it sounds like from our initial investigation here on scene there was a disagreement of some sort between two parties, and unfortunately, they chose to resolve that with guns,” St. Lucie County Chief Deputy Brian Hester said.

Police said four people, including a child, sustained non-life-threatening injuries during the ensuing confusion, the station reported.

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