(CBS/AP) LONG BEACH, Calif - Authorities say they have no immediate plans for arrests after an 11-year-old girl died following a school fight at a Long Beach elementary school Friday.
Police said Saturday night that the girl, Joanna Ramos, died at a hospital hours after the fight with another 11-year-old girl outside her school.
Law enforcement officials stressed the unusual nature of the tragedy and are urging caution about linking the girl's death to the fight pending a coroner's report on the cause of death.
The Los Angeles Times reports Ramos complained that her head hurt after the altercation Friday, a friend said.
Long Beach police on Sunday were trying to determine exactly what happened and said no arrests have been made.
"There are still many questions, many questions that cannot be answered," said Long Beach Deputy Police Chief Robert Luna.
"I think it's safe to say this is definitely an isolated incident," police spokeswoman Nancy Pratt said. "I personally don't hear of 11-year-old fights like this, especially girls. I can't say they never happen but I think everyone was completely caught off-guard by this event."
The fight didn't appear to be especially serious or violent, police said. No weapons were used and neither girl was knocked to the ground. Authorities could not say what sparked the fight but friends of the girls had their suspicions.
"They were fighting over a boy," said Stephanie Guadalupe, a friend of Joanna. "I told the teacher and she said she would talk to all the girls on Monday."
The students involved in the altercation left an after-school program and went to an alley near the school to fight.
One friend, Maggie Martinez, said she broke up the fight. "She did not hit her head. The other girl just punched her in the face. She started bleeding from the nose."
Long Beach Unified School District Superintendent Chris Steinhauser said that though the fight appeared to be pre-planned, but there was no indication that adults at the school, which has about 800 students in kindergarten through fifth grade, were aware of it beforehand.
Adults later noticed Joanna wasn't feeling well, complaining of a headache, and drove her to a local emergency room.
Martinez said she got a frantic call from the Ramos' mother and told her she "died three times in the car" on the way to the hospital, but her mother was able to revive her. "She did the CPR and she revived. But when they got to the hospital they said it was really bad and they would have to do brain surgery on her."
She was hospitalized and had surgery but died about six hours after the fight at 9 p.m. on Friday.
Police were investigating and have interviewed the girl who fought with Ramos.