(CNN) -- A Florida teen accused of fatally shooting a 13-year-old girl on a private school bus has been charged with manslaughter, police said Wednesday.
"The defendant removed a firearm that was concealed in his backpack and began displaying it," the Miami Dade Police arrest report said. He "discharged the firearm one time, shooting the victim."
The shooting happened as the bus was traveling down a road in Homestead, Florida, the report said.
Lourdes Guzman, who suffered a gunshot wound, was airlifted to Miami Children's Hospital, where she died, the police report said.
Eight children on the bus, including the victim's 7-year-old sibling, witnessed the shooting, police said. The bus was not equipped with surveillance cameras.
Although police released the 15-year-old male suspect's name, CNN policy is not to identify a minor in most cases.
"The motive at this time is unknown as well as any information regarding the firearm," the police report said.
CNN's Nick Valencia contributed to this report.