Police were searching Saturday for a person who shot and killed a 16-year-old girl and wounded two men when firing into a crowd following a football game at a high school in Southern California.

The girl, a student at Woodrow Wilson High School, died at a hospital. It was unclear what led to Friday night's shooting at the school in Long Beach, police Sgt. Dina Zapalski said.

Gunfire erupted around 10 p.m., as several hundred people filed out of the homecoming game against arch-rival Polytechnic High School.

Family members identified the girl as Melody Ross. City Councilman Gary DeLong described Ross as "an innocent bystander who was not involved" in the altercation.

Ross was an honor student and track athlete who was dressed as Supergirl for the Halloween eve game, friends and school officials said.

"It's very disconcerting. I'm sick to my stomach when something like that happens and you have an innocent kid involved," Wilson football coach Mario Morales. He said he heard between five and seven shots as he was leaving the stadium after his team's loss.

A school dance with about 200 students had begun when the shots were fired. The dance was locked down while police searched the campus for suspects, said Long Beach Unified School District spokesman Chris Eftychiou. Eftychiou said extra security was on hand for the rivalry game but police told school authorities there was no indication the shooting had anything to do with bad blood between the schools.

An 18-year-old man and a 20-year-old man were hospitalized with non-life-threatening injuries, police said. The two men were not students, according to DeLong.

Friends and family members erected a makeshift memorial with flowers and hand-written notes to Ross on a street near the school.

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