Northern California was under a rare and brief tsunami warning alert Thursday that tested local emergency notification systems after a 7.0 magnitude earthquake shook part of the state.

County officials announced Friday they are overhauling their emergency alert system after residents across the Los Angeles area continued to receive erroneous emergency alerts that urged them to ...

ShakeAlertLA will give warnings similar to an Amber Alert when significant shaking starts nearby, ideally allowing users to get to a safe place, according to the app. An earthquake early ...