The incident happened at Club Blu in Fort Myers. The gunshots were fired in the clubs parking lot at around 12:30 a.m. ET. The club had been hosting a "teen night".
Fort Myers Police Department said in a statement that "at least 14-16 people" were wounded in the shooting, with their injuries ranging from minor to life-threatening. Two people were short dead, reportedly male.
Lee Memorial Hospital spokeswoman confirms ages of shooting victims being treated at hospital range from 12 to 27.
Three people have been detained for questioning, according to police. It isn't clear if more people are involved.
Witnesses told media there had been an argument outside the club, which was reportedly hosting an event for teenagers, before the shooting. A motive is still not known. Witnesses described how someone just "kept shooting" during the attack, which happened in the club's car park.
Police also reported about two other scenes, connected with the incident. One involved a house that was shot at where there was one minor injury, and another was where a "person of interest" had been detained in connection with the shooting, authorities said.
Police are still "actively canvassing" the area to look for other people who might be involved in the attack. They are still working to determine the motive for the incident.