It happened on June 3, right after a ceremony for the Sem Yeto Continuation School on the Fairfield High School campus.
RELATED: Fairfield police identify 18-year-old victim in deadly graduation shooting that injured 3 others
Police say a 17-year-old shot and killed an 18-year-old who had just received his diploma.
The 18-year-old killed was identified as Jamario Baker. Three other people -- ages 11, 20 and 25 -- were also injured in the shooting.
Fairfield police say witnesses came forward and alerted them that the suspect had fled to Texas.
He was arrested Friday morning in the Dallas area and will be extradited to Solano County to face charges.
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