Mass panic has been sparked as millions of phones, TVs and radios sounded a warning.
The United States was braced for the alert as Federal Emergency Management Agency tested its National Wireless Emergency Alert System.
FEMA had warned 'seconds count in disasters' as it justifies the nationwide test and people have been urged not to become concerned with an alert on their phones, warning them of impending danger - as it is just a practice run.
The Integrated Public Alert and Warning System will send out warnings to people's phones later today as the federal government tests its emergency alert system. Messages will be sent via the Emergency Alert System and Wireless Emergency Alerts. It will test the system designed to allow the American president to speak to citizens within 10 minutes amid a national emergency. It will begin at 2.20pm Eastern Time later today and will be conducted over a 30-minute window.
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"THIS IS A TEST of the National Wireless Emergency Alert System," the message will read. "No action is needed." Phones will vibrate and make a noise, whose mobile devices in Spanish will receive the notification in Spanish. The test has spurred falsehoods on social media that it's part of a plot to send a signal to cell phones nationwide in order to activate nanoparticles such as graphene oxide that have been introduced into peopleâs bodies. This is not true.
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