Los Angeles County Sheriff’s Department Homicide Investigators are continuing their investigation into the circumstances surrounding an in-custody death involving the Claremont Police Department.
On Friday, November 28, 2025, at approximately 1518 hours, the Claremont Police Department received two calls of a male acting erratically and possibly under the influence of narcotics, in the area of Claremont Boulevard and Andrew Drive. One caller reported the male entered a vehicle and left the location. As officers arrived in the area, they observed the male driving, and they conducted a traffic stop. Based on the male’s behavior, officers believed he was operating a motor vehicle while under the influence. The officers asked the male to step out of the vehicle, at which point a use-of-force incident occurred.
During the encounter, the male became unresponsive. Officers immediately initiated lifesaving measures. The Los Angeles County Fire Department arrived on scene and continued emergency medical treatment. The male was transported by ambulance to Pomona Valley Hospital Medical Center, where he was later pronounced deceased.
The male was later identified as 30-year-old Diego Alfonso Rios from the city of Rancho Cucamonga. The cause of death will be determined by the Los Angeles County Medical Examiner’s Office.
There is no further information at this time.
If you prefer to provide information anonymously, you may call "Crime Stoppers" by dialing (800) 222-TIPS (8477), use your smartphone by downloading the “P3 Tips” Mobile APP on Google play or the Apple App Store or by using the website http://lacrimestoppers.org.
Anyone with information about this incident is encouraged to contact the Los Angeles County Sheriff's Department's Homicide Bureau at (323) 890-5500. If you prefer to provide information anonymously, you may call "Crime Stoppers" by dialing (800) 222-TIPS (8477), use your smartphone by downloading the “P3 Tips” Mobile APP on Google play or the Apple App Store or by using the website http://lacrimestoppers.org
Forwarded by:
Sheriff's Information Bureau
Los Angeles County Sheriff's Department
211 West Temple Street
Los Angeles California 90012
http://www.lasd.org
213-229-1700
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Robert G. Luna, Sheriff
Los Angeles County Sheriff's Department
