Sean Archilles, 14 and Stef'An Strawder, 18 identified as victims of Club Blu Teen Party in Florida

Sean McIntryre/New York Times (Family of Sean Archilles)

A Facebook user calling herself Juss Olivia posted a video shortly after the shooting, saying she had been sitting in a car across the street, near her apartment, when she heard gunfire and saw about five people “spraying nonstop, running and shooting.” She and her friends said they had joined a crowd fleeing on foot and ducking behind cars.

The authorities identified the two victims who were killed as Sean Archilles, 14, and Stef’An Strawder, 18, both budding basketball stars who had just left the club.

Sean, a student at Royal Palm Exceptional School, was shot in the parking lot, and a girl with him was shot in a leg, said his brothers, John and Verly Francois. They stood outside their mother’s house, where family and friends had gathered to comfort her, and said it was hard to believe that an innocent outing with friends had ended in the death of their youngest brother.

“They were just walking to a friend’s house about a block away,” said John Francois, 19.

Sean, the youngest of four brothers, stood just 5-foot-6, but he was a basketball fanatic whose brothers called him “Baby Kevin Durant” because he looked so much like the N.B.A. star and always had a basketball in his hand.

“He really was like Kevin Durant; he could have been his son,” Mr. Francois said. “He loved to play basketball. He was always down for that. That, or chilling at home.”

With files from the New York Times