SAN MATEO (CBS SF) — A person was shot dead in San Mateo Monday over an apparent love triangle, prompting an hours-long standoff with the suspect for several hours until he was discovered dead by a self-inflicted gunshot wound, police said.

San Mateo police said officers responding to a shooting at a care home on the 1700 block of Pierce Street at 7:20 a.m. found a 42-year-old man who was shot multiple times. The suspect was identified as a 48-year-old man who was a co-worker of the victim, and police said the motive appears to be over a dating relationship they both shared with a woman.

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Police identified the suspect and his location at his own home a mile away on the 1600 block of Marina Court within minutes of the shooting.

Officers immediately began negotiations with him with the help of a SWAT team and a crisis negotiation team. Negotiators learned the suspect’s wife was inside the home voluntarily and also worked to convince her husband to surrender peacefully.

At 12:12 p.m. after more than four hours of negotiations, officers heard the sound of one gunshot while on the phone with the homicide suspect. After the suspect’s wife exited the home unharmed, a robot was sent into the suspect’s room where he was found dead of a self-inflicted gunshot wound.

Police said the suspect and victim would be identified by the coroner’s office.

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A police spokesperson said the homicide does not appear to be related to an October 30th shooting that killed a man and injured a young child, or the rash of shootings that resulted from it.

Investigators urged anyone with information or security footage related to the case to contact Detective Sergeant Lee Violett at (650) 522-7662 or Anonymous tips can be submitted to or by calling (650) 522-7676.


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