HOMESTEAD, Fla. -- A 13-year-old girl was shot and killed on a Homestead school bus Tuesday morning, and another student has been arrested as the suspected shooter, authorities said.
It's not clear if the gun accidentally discharged or was fired on purpose. A firearm was recovered from the scene.
The victim, identified as Lourdes Guzman-DeJesus, was airlifted to Miami Children's Hospital where she was pronounced dead. She was at student at Palm Glades Preparatory Academy.
The shooting happened around 6:45 a.m. at 137th Avenue near 288th Street. 137th Avenue remains shut down this afternoon.
Nine children were on the bus at the time, including the victim's 7-year-old sister. Parents with students on the bus rushed to see if they were okay.
"It is scary to find out your kids are in this, you never expect it. You expect them to go to school safe," says Maria Romero, who was visibly shaken.
A motive hadn't been determined Tuesday, and police were investigating the relationship between the shooter and the victim, Officer Alvaro Zabaleta told reporters.
"It's traumatic for them for what they had to witness to begin with and now you're going to have to question them to ask them exactly what they saw," Zabaleta told CNN affiliate WPLG. "You know, it's tragic. Anytime it deals with a child, and then, of course, when we get the phone call that they confirmed that she passed away, it's very sad."
None of the other children on the bus was injured, and all parties present at the shooting were taken to the homicide bureau for questioning, police said.
"We're dealing with small children so the questioning process is going to be a lot different... they're already shaken up of course with what they just had to witness and on top of that you have to question them. So, this is going to take a very slow and tedious process, we have to take into account these are children we're talking to," said Alvaro Zabaleta, Miami-Dade County Police Public Information Officer.
Several parents went to pick up their kids at Palm Glades school early when they heard the news.
"When I heard it gave me chills up my body that a 13 year old would lose her life like that, it was heart wrenching," says Rynell Atkins, parent of a Palm Glades student.
Police didn't have further information Tuesday on the firearm used in the shooting.
CNN contributed to this report.