LASD Deputy-Involved Shooting (DIS) in the 44500 block of 15th Street West, Lancaster.
The following information is based on facts determined from an investigation into the incident described.
The investigation is ongoing and as witnesses are interviewed, evidence is analyzed and reports are reviewed, our understanding of the facts may change. The details described below accurately reflect the facts as we currently know them.
On September 7, 2026, at approximately 9:46 a.m., Lancaster Station deputies responded to the 44500 block of 15th Street West, Lancaster, regarding a domestic violence incident. Information provided in the call indicated that a male was arguing with a female and attempting to force her into a vehicle. Prior the deputies’ arrival, the call was updated indicating the male was armed with a handgun. The male was later identified as 29-year-old Derek Barrientos.
Deputies arrived on scene and located Barrientos in front of the location. Barrientos was armed with a handgun and had his arm around the neck of the victim, his estranged wife. Barrientos pointed the handgun at the victim, at himself, and at deputies, resulting in a deputy-involved shooting.
Barrientos was struck by gunfire and dropped his gun. Deputies rendered medical aid to Barrientos until the arrival of Los Angeles County Fire Department personnel. Barrientos was subsequently transported to a local hospital where he received medical treatment.
No deputies or other people were injured during this incident.
A 9mm semi-automatic handgun with a loaded magazine was recovered at the scene.
LASD Homicide investigators responded to the scene to conduct interviews, follow up, and process the scene. Representatives from the Internal Affairs Bureau (IAB), and the Los Angeles County District Attorney’s Office, Justice System Integrity Division (JSID) also responded and monitored the investigation.
Once completed, the investigation will be forwarded to the District Attorney’s Office to determine if the force used by the involved personnel was lawful. Once the District Attorney’s Office investigation is completed, the LASD will evaluate the actions of the personnel within the application of policy, procedures, and tactics.
Anyone with information regarding this incident is encouraged to call Sheriff’s Homicide at 323-890-5500. Anonymous tips may be received through CRIMESTOPPERS at 800-222-8477.
The employees involved in the deputy-involved shooting are identified as Deputy Louie Herrera and Deputy Abraham Rosales.
