<div class="css-s99gbd StoryBodyCompanionColumn" data-testid="companionColumn-0"><div class="css-53u6y8"><p class="css-ac37hb evys1bk0">More than a year before Caleb Vazquez and a friend attacked a mosque in San Diego and killed three people, the police were so alarmed by Mr. Vazquez’s behavior that they secured a court order to confiscate his father’s guns.</p><p class="css-ac37hb evys1bk0">“Child was involved in suspicious behavior idolizing nazis and mass shooters,” a police officer wrote in a January 2025 protective order.</p><p class="css-ac37hb evys1bk0">Mr. Vazquez, who was found dead on Monday shortly after the police say he and a friend attacked the Islamic Center of San Diego, had at some point been placed in an involuntary psychiatric hold, according to documents filed at San Diego Superior Court.</p><p class="css-ac37hb evys1bk0">The court papers show that Mr. Vazquez, 18, had been on the authorities’ radar long before the shooting at the mosque. They also raise questions about why the authorities, with their knowledge, were unable to prevent the massacre.</p></div><aside aria-label="companion column" class="css-ew4tgv"></aside></div><div data-testid="Dropzone-1"></div><div class="css-s99gbd StoryBodyCompanionColumn" data-testid="companionColumn-1"><div class="css-53u6y8"><p class="css-ac37hb evys1bk0">The California Legislature in 2014 allowed the family and friends of people who might be violent, as well as the police and other parties, to seek a court order to temporarily confiscate weapons through measures known as gun violence restraining orders. The law was a response to a mass shooting that year near the campus of the University of California, Santa Barbara.</p><p class="css-ac37hb evys1bk0">The order to take guns from the Vazquez household was filed against Mr. Vazquez’s father, Marco Vazquez. The court documents show that Marco Vazquez and his wife, Lilliana Vazquez, had 26 guns, including pistols, rifles and shotguns.</p><div class="css-kbghgg"><div class="css-121kum4"><div class="css-171d1bw"></div><div class="css-asuuk5"><noscript><div class="css-7axq9l" data-testid="optimistic-truncator-noscript"><svg aria-hidden="true" class="css-1u67kh9" data-tpl="i" height="24" viewbox="0 0 24 24" width="24"><path clip-rule="evenodd" d="M2.5 12a9.5 9.5 0 1 1 19 0 9.5 9.5 0 0 1-19 0Zm8.5 1.75v-7.5h2v7.5h-2Zm0 2v2h2v-2h-2Z" fill="currentColor" fill-rule="evenodd"></path></svg><div class="css-6yo1no" data-testid="optimistic-truncator-noscript-message"><p class="css-3kpklk" data-tpl="t">We are having trouble retrieving the article content.</p><p class="css-3kpklk" data-tpl="t">Please enable JavaScript in your browser settings.</p></div></div></noscript><div class="css-1dv1kvn" id="optimistic-truncator-a11y" tabindex="-1"><hr/><p>Thank you for your patience while we verify access. 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