[1/5] Police officers detain a man, believed by law enforcement to be the Half Moon Bay mass shooting suspect, in Half Moon Bay, California, U.S., January 23, 2023, in this screengrab taken from a social media video.
California Governor Gavin Newsom said he was visiting wounded survivors from Saturday night's massacre in the Los Angeles suburb of Monterey Park when he was informed of Monday's killings in northern California.
A semi-automatic handgun was found in his car, San Mateo County Sheriff Christina Corpus told an evening news conference.
It ranked as the deadliest mass shooting ever in Los Angeles County, according to Hilda Solis, a member of the county Board of Supervisors.
Monterey Park Police Chief Scott Wiese said investigators were looking into unconfirmed reports that the violence may have been precipitated by jealousy or relationship issues.