Hernandez said his sister-in-law's husband was a friend of the building manager.
Marcela Chavarri, director of the American Christian School, said Priscila Perez was about to enter her senior year at the school.
"She was a lovely girl," Chavarri said through tears. "She was always happy and helping her classmates."
In Hialeah — a suburb of about 230,000 residents, about three-quarters of whom are Cuban or Cuban-American — the street in the quiet, apartment-building-lined neighborhood was still blocked by tape Saturday afternoon.
The building where the standoff occurred is an aging, beige structure with an open terrace in the middle. It has 90 to 95 units. The apartment where neighbors said the shooting started was charred, the door and ceiling immediately outside burned black.
Zogby called the whole building a crime scene. "He probably fired dozens of shots during the whole incident," he said.
"It could have been a much, much more dangerous situation."