(WASHINGTON) -- The federal government unveiled a major upgrade Tuesday of the national emergency alert system that will send warnings directly to cellphone users.
Similar to the alerts heard over the radio and on TV -- a loud, piercing sound followed by the words "This is a test of the national emergency alert system" -- the new alerts will be sent via text messages. They will inform cellphone users of alerts issued by the president, emergencies like natural disasters that pose an imminent threat, and cases of child abductions or missing children.
Called the Personal Localized Alerting Network (PLAN), the expanded service will work on newer cellphones that contain a special chip. The text messages will be free of charge and will be available to customers of AT&T, Verizon, Sprint and T-Mobile.
The alerts are scheduled to be rolled out in New York and Washington, D.C. later this year, with a nationwide launch to follow by next spring.
Copyright 2011 ABC News Radio