Recent instances of emergency alert systems causing public alarm have drawn attention to their fallibility, with several past failures offering context.
In January 2018, Hawaii's emergency management agency mistakenly sent an alert warning of an incoming ballistic missile to over a million people. The false alarm, triggered by an employee pushing the wrong buttons during an internal drill, caused widespread panic, with residents and tourists seeking immediate shelter. The alert was corrected on Twitter 12 minutes later, but a confirmation of the false alarm via phone alert took 38 minutes. Experts noted the system lacked a template for retraction, requiring manual entry for the all-clear message.
More recently, in January 2025, Los Angeles County experienced chaos when 9.6 million residents received an evacuation alert intended for the West Hills area. The alert, issued due to a technical error, was mistakenly broadcast countywide. Los Angeles County Supervisor Janice Hahn acknowledged the mistake, stating a correction would be issued shortly. The incident led to public frustration and criticism of the system's reliability.
Another type of failure occurred in Dallas in April 2017, when the city's emergency siren system was hacked. Hackers activated all 156 sirens for 1.5 hours overnight, typically used for severe weather warnings, leading to a surge in 911 calls and leaving residents shaken. City officials eventually had to shut down the system to regain control.
In the United Kingdom in 2023, a test emergency alert intended for millions of mobile users experienced issues. While most networks successfully broadcast the alert, customers on the Three network did not receive it at all, while some received it prematurely. This was attributed to a configuration error on the Three network, which sent the alert only once at a specific time, rather than at regular intervals to ensure widespread reception.
These incidents illustrate a pattern of technical errors, human mistakes, and external interference that can compromise the effectiveness and public trust in emergency alert systems. Instructions on how to disable severe and extreme alerts are available on both iPhone and Android devices for users who wish to opt out of receiving such notifications.