Sophomore Amanda Collette was confirmed dead after being discovered on a hallway floor by a school resource officer at Dillard High School around 11 a.m. Another 15-year-old girl was being held and questioned by police in the death.
"This is a situation where we are more than heartbroken," said Jim Notter, the superintendent of schools for Broward County.
The discovery of the body started a confusing series of events. Police said they did not believe gunshots were heard, and an initial examination found no major wound on the girl's body, leading to questions about whether or not she was shot.
Authorities later confirmed there was a shooting, but Sgt. Frank Sousa, a spokesman for the Fort Lauderdale Police, said it was possible a smaller-caliber gun was used and the wound closed around the bullet.
Police said no other students were believed to have been involved.
"This appears to be an isolated incident," said Sousa.
Stephan Willis, a sophomore who said he witnessed the shooting, said the girls were arguing in an outside corridor when the suspect suddenly produced a gun and shot Collette.
"She's a nice girl. She's quiet. She just keeps to herself," said Willis, who said he had known the victim since elementary school.
Another student, 14-year-old freshman Hermond Davis, said the hallway was crowded after Collette collapsed and students screamed and panicked.
"As I am walking to the cafeteria, I saw this girl collapsed," Davis said. "She just fell, she just fell right out of the sky."
The suspect was apprehended at an area restaurant after a caller there reported she may have been involved in a school shooting. A gun was recovered.
The school was locked down for a short time, but classes soon resumed. Still, as police were announcing the fatality, gates were chain-locked and access was being restricted as a news helicopter hovered overhead. Several dozen parents gathered outside, some openly weeping.
"I'm just trying to get my baby out of here," said Betty Barnes, whose 15-year-old daughter, Tiffany, is a sophomore at the school. "I want to make sure she's OK. It's very scary not knowing."
Dillard has about 1,700 students. They don't pass through metal detectors, but officers are stationed on campus and security cameras are placed throughout.