Corona police arrested two 15-year-old girls on October 6, 2026, after the FBI flagged social media communications threatening Corona High School in Riverside County. One was picked up at Corona High, the other at nearby Norco High. Investigators say the pair spent months researching school shootings and discussing an attack on an unspecified future date, though no guns were recovered. Both remain in custody on conspiracy to commit murder charges while the Riverside County District Attorney's Office reviews the case. Coverage has since established that Meta flagged the girls' messages on its own and sent them to the FBI, which forwarded them to local police.