Santa Clara police are asking for the public's help finding a 59-year-old man who vanished yesterday afternoon near a busy stretch of North Winchester Boulevard, not far from Santana Row and the San Jose border. Seth Klein was last seen around 1 p.m. on the 400 block of North Winchester Boulevard, wearing a blue polo shirt and gray or tan pants, according to police. He has brown/gray hair, brown eyes, stands 5 feet 11 inches tall, and weighs approximately 245 pounds.
The department issued a Nixle notification early today, at 5:19 a.m., formally classifying Klein as an at-risk missing adult and requesting public assistance in locating him. In a Santa Clara Police post on X, the agency asked anyone who sees Klein or has information about his whereabouts to call 911 immediately. The 400 block of North Winchester Boulevard sits near local landmarks, including Church of the Valley and the Stratford School's Winchester campus, an area with steady foot traffic close to major commercial hubs like Santana Row and Westfield Valley Fair, according to Church of the Valley.
MISSING AT RISK ADULT, PUBLIC ASSISTANCE REQUESTED
— Santa Clara Police (@SantaClaraPD) August 10, 2026
https://t.co/encvDCD20Z
What the At-Risk Designation Means
Under California Penal Code Section 14215, an individual can be classified as an at-risk missing person if they are cognitively or mentally impaired, in need of medical attention, have no prior pattern of disappearing, or are suspected to be a victim of foul play, according to FindLaw. That classification shapes how quickly and how broadly police mobilize resources, though the department has not said which of those criteria applies to Klein's case. California law also prohibits police from imposing any waiting period before accepting a missing person report, per the same source, meaning officers were obligated to act on Klein's case immediately rather than delay the investigation.
State law further requires that at-risk missing person cases be entered into state and national databases within two hours of the report being taken, according to CalAlerts. That rapid entry into the CLETS and NCIC systems is designed to give law enforcement agencies across the state and country visibility into Klein's case within hours of his disappearance, rather than days.
Escalation Options Still on the Table
It remains unclear whether the California Highway Patrol has been asked to issue a statewide Silver Alert for Klein. Under California Government Code Section 8594.10, a Silver Alert can be requested through CHP when a missing person is developmentally disabled, cognitively impaired, or 65 or older and determined to be in peril, according to the California Highway Patrol. Such an alert would allow CHP to broadcast warnings on electronic freeway signs and through regional media outlets, significantly widening the search beyond Santa Clara. Whether Klein suffers from a medical or cognitive condition requiring medication, and whether search efforts are concentrating on nearby retail hubs or transit points, are open questions police have not yet addressed publicly.
Santa Clara police also reminded the public that matters requiring police, fire, or medical assistance should not be reported on Twitter, directing anyone with information to call 911 or the department's non-emergency line at 408-615-5580. The Santa Clara Police Department is located at 601 El Camino Real.
A Familiar Pattern for South Bay Searches
Missing adult cases are a routine part of public safety work in the South Bay. Santa Clara County agencies received 1,743 reports of missing adults in 2023, according to California Department of Justice data cited by Hoodline. Statewide, 35,859 adult missing person reports were filed in 2025, with 16,551 individuals located by law enforcement and another 12,709 returning on their own, per the California Department of Justice. Roughly 70 percent of reported missing persons in California are located or voluntarily return within 48 to 72 hours, according to the San Fernando Valley News Portal, underscoring why early public notification matters.
Santa Clara police have relied on this same public-alert playbook before. In August 2024, the department sought public help finding missing at-risk adult Renata Lopes. Similar cases have played out across the county in recent days, including the search for missing teen Damien Padilla and the recovery of 84-year-old Fe Umali after she vanished from the Milpitas Great Mall. For now, Klein remains missing, and Santa Clara police say the public's eyes and tips are what they need most to bring the search to a resolution.
