By Holly Yan, Laura Sharman, Diego Mendoza, CNN
(CNN) — Investigators are searching for whoever killed an 18-year-old and wounded three other people shortly after a high school graduation ceremony in California’s Bay Area.
The gunfire erupted Wednesday after the ceremony for Sem Yeto High School, which started at 6 p.m. The alternative school shares a campus with Fairfield High School, about 50 miles northeast of San Francisco.
At about 7:15 p.m., authorities responded to a shooting in the parking lot of Fairfield High School, police said.
“Three victims, ages 11, 20, and 25, sustained non-fatal gunshot injuries. A fourth victim, an 18-year-old, succumbed to their injuries,” Fairfield Police Officer Michelle Belyea said Thursday.
The 11-year-old is recovering at a local hospital, police said.
Police are not publicly identifying the mass shooting victims “pending next-of-kin notification and to protect the integrity of the ongoing investigation,” Belyea said.
CNN has asked the school district whether the 18-year-old who was killed had just graduated from Sem Yeto High School minutes earlier.
The shooting is one of at least 168 mass shootings in the US this year, according to the Gun Violence Archive, which defines a mass shooting as one in which four or more victims are shot.
‘Hundreds of potential witnesses’ but no arrests
About 1,000 people attended the graduation ceremony, “with hundreds of potential witnesses to this tragedy,” Belyea said.
Detectives are “identifying and interviewing these witnesses” and “are working diligently to identify those responsible,” Belyea said. She asked anyone with information to contact Fairfield police.
Authorities did not answer CNN’s questions about whether the attack was targeted or random, or what the motive might be.
“As this is an on-going investigation, no additional information is available for release,” police said in a statement.
Graduation photos, then bullets
The shots rang out as photos were being taken in the school parking lot where students had gathered to congratulate one another and meet up with their families, one witness told CNN.
“While I was taking pictures with a graduate and her family, I heard about five loud popping sounds,” the witness said, speaking on condition of anonymity.
“People seemed confused at first and then quickly panicked once they realized something was wrong.”
The witness did not see the shooter, or the direction of the gunfire, but recalled “about five objects on the ground that appeared to be shell casings” and damage to several vehicles.
“What happened was heartbreaking and deeply unsettling. A place where students and families had just come together to celebrate should have been safe.”
Amanda Prieto, who lives near the school, told CNN affiliate KCRA she was on the phone in her backyard when she heard the gunfire. She was “immediately terrified” by the sound of shots from the school her 17-year-old son attends.
“I looked over the fence, and people were just screaming and running through the parking lot,” she told KCRA. “It was horrific.”
A rite of passage marred
Thursday was supposed to be a celebratory last day of school for the 20,000 students in the Fairfield-Suisun Unified School District. Instead, it was overshadowed by grief from the tragedy outside Fairfield High.
“Today, our focus is on supporting our students, staff, and families as they process what occurred,” the school district wrote in a letter to the community Thursday. “Caring educators and mental health support is available at our sites. We encourage anyone who needs support to reach out to their schools.”
We are also in direct communication with school district leadership regarding security planning and public safety considerations for all remaining graduation ceremonies
Seniors from Fairfield High, who are set to graduate Friday evening, won’t walk across a stage at their own school.
“Out of respect for our grieving community, we have decided to move tomorrow’s Fairfield High Class of 2026 graduation ceremonies to the Armijo High School Stadium,” the school district said.
The Fairfield Police Department said Thursday it will increase the number of officers assigned to several upcoming graduation ceremonies hosted by the Fairfield-Suisun Unified School District, with additional law enforcement resources provided by partners. The department also said it has communicated with school district leadership about security planning and public safety at the events.
“We want our community to know that we are thinking deeply about everyone impacted by last night’s events. Our hearts are with our graduates, their families, and all those who attended the ceremony expecting to celebrate an important milestone together,” the district said.
This story has been updated with additional information.
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