Dozens of students gathered before classes to hold an impromptu memorial service for a 15-year-old girl who was gunned down in a Ft. Lauderdale school hallway.

Teah Wimberly, 15, was charged with first-degree murder and discharging a weapon on Dillard High School property in the death of Amanda Collette, also 15. The shooting happened during an apparent argument between the two on Wednesday.

During Thursday's service, some of the teens wore black, others brought flowers and teddy bears, as they held hands around a concrete circle next to three flag poles outside the school.

No other students were believed to have been involved in the incident, and the motive is still being investigated, police said.

The body of Collette, a sophomore, was found on a hallway floor at Dillard High School around 11 a.m. She was shot in the torso while students were changing classes.

"This is a situation where we are more than heartbroken," said Jim Notter, the superintendent of schools for Broward County.

Wimberly left campus and walked across the street to a restaurant called Captain Crab's Take-Away where she called authorities and told them that "she had shot her friend," said Sgt. Frank Sousa, a Ft. Lauderdale police spokesman. Authorities took her into custody at the restaurant and recovered a gun.

The discovery of the body started a confusing series of events. Police said they did not believe anyone heard gunshots, 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 the shooting and Sousa said it was possible a smaller-caliber gun was used and the wound closed around the bullet.

"This appears to be an isolated incident," Sousa said.

Stephan Willis, a sophomore who said he witnessed the shooting, said the girls were arguing in an outside corridor when Wimberly suddenly produced a gun and shot Collette.

"She's a nice girl. She's quiet. She just keeps to herself," Willis said of Collette. He said he had known the victim since elementary school.

Another student, 14-year-old freshman Hermond Davis, said the outside 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 school was locked down for a brief period of time, but classes resumed shortly thereafter.

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.

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