3 separate shootings mar St. Patrick's Day festivities in Jacksonville Beach, Fla.

Police are searching for multiple suspects in three different shootings that left one person dead and at least three injured as thousands crowded in downtown Jacksonville Beach, Florida, Sunday night for St. Patrick's Day festivities.

The shootings occurred near the city's beachfront after police broke up a group of up to 400 people in their late teens who gathered under the pier Sunday afternoon.

"This group engaged in boxing matches, fights and other incidents. The Jacksonville Beach Police Department had to take action," Jacksonville Beach Police Chief Gene Paul Smith said at a new conference on Monday morning. "When the crowd dispersed, that's when the shooting happened."

Police responded to the first shooting at a Best Western hotel at around 7:50 p.m., Smith said. The shooting left three people injured – two were transported to the hospital afterward, and another self-reported an injury. Authorities believe two of the victims fired at each other, while the third was an innocent bystander, Smith said.

Less than half an hour later, reports came in of a second shooting in a parking lot outside the Ritz, a cocktail bar. No one was injured or killed, and the shooter fled the scene in a black ski mask, Smith said. Officers found one firearm.

Police responded to the third shooting, which left one victim dead, at Sneakers Sports Grille at 8:31 p.m. Officers believe three suspects pulled out firearms, Smith said. The identity of the 21-year-old victim has not been released.

The shootings are believed to be unrelated, Smith said. The investigation remains ongoing, and the identities of the suspects have not been released.

"Quite frankly, I'm pissed off," Smith said. "I want you to come to Jacksonville Beach, I want you to live here, I want you to visit, but if you break the law, we're going to put you in jail."

Smith said officials do not know if any of the shootings were gang-related. The victim who self-reported an injury in the first shooting is a known gang member, he said.

Jacksonville police have asked people to contact authorities if they have information related to the incidents.