Jordan Davis, 17, was hit at least twice by bullets fired by Michael Dunn, a 45-year-old businessman who is in custody over the incident which took place Friday in Jacksonville, said Sheriff's Department Lieutenant Rob Schoonover.
The shooting occurred after Dunn, who is white, approached Davis, who was black, to complain about loud music coming from the sport utility vehicle (SUV) in which the youngsters were seated.
"Jordan and Dunn exchanged words, and Dunn pulled a gun and shot eight or nine times, striking Jordan twice. No one else was hurt," said Schoonover.
No firearms were found in the victim's car.
Dunn, whose girlfriend was buying in a convenience store when the incident occurred, was in town for his son's wedding. He left the scene and returned to his hotel but he was later traced from closed-circuit television footage.
Ron Davis, the victim's father, told local television that he wants to see justice done, "whether it be through the legal system," or God.
"God's going to punish him for that, so me, I don't want to do anything to him," Davis told the WAWS television channel.
In February, racial tensions soared in Florida when unarmed black teenager Trayvon Martin was shot dead by Hispanic neighbourhood watch coordinator George Zimmerman.