(CBS) — Friends, classmates and family filled a West Side church Saturday to remember Demetrius Griffin — the 15-year-old Steinmetz High School student who was murdered by a gunshot wound to the head and set on fire in an Austin alley last month.

The service, at the New Mount Pilgrim Missionary Baptist Church, opened with a declaration by the Stars of Heaven singers that “Chicago is in need of help.”

Brunson Math and Science Academy Principal Carol Wilson said until he graduated in June, Demetrius was everything from assembly set-up manager to distribution manager.

Wilson had to compose herself as she told attendees she had imagined many times Demetrius would grow up to become a stagehand and eventually the stage manager for a major Chicago theater.

“Demetrius mattered,” said New Mount Pilgrim’s pastor, the Rev. Marshall Hatch.

Speakers called on those who know who killed him to turn in the killer. The Leaders’ Network ministers have offered a $2,500 reward for information that leads to the arrest and conviction of the killer.

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