OXNARD, Calif. — Hundreds of mourners gathered at a church here on Friday to remember an eighth-grade boy who was shot to death inside a junior high school computer lab by a fellow student in what prosecutors are calling a hate crime.

In recent weeks, the victim, Lawrence King, 15, had said publicly that he was gay, classmates said, enduring harassment from a group of schoolmates, including the 14-year-old boy charged in his death.

The gunman, identified by the police as Brandon McInerney, “is just as much a victim as Lawrence,” said Masen Davis, executive director of the Transgender Law Center. “He’s a victim of homophobia and hate.”

Mr. Davis said “more and more kids are coming out in junior high school and expressing gender different identities at younger ages.”

Prosecutors charged Brandon as an adult with murder as a premeditated hate crime and gun possession. If convicted, he faces a sentence of 52 years to life in prison.