JACKSONVILLE, Fla. -- When children are abducted, and Amber Alerts are issued, cell phones make a loud and distinct sound.
"It sounded like a screeching sound from a train," said Git Tham, describing a noise that startled him Friday, that he couldn't ignore.
The sound was an alert from the Florida Department of Law Enforcement that 6-year-old old Onnika Fisher was allegedly abducted by her mother, Charity Chatman, during a supervised visit.
"It kinda scared me," said Tran. "I didn't know what was going on. I've never heard my phone do that before."
But many others didn't get that startling message, and Action News wanted to know why.
Jay Howell, founder of the National Center for Missing and Exploited Children, says technology is one reason Amber Alerts have resulted in more than 600 children returning home, including little Onnika, who was found in Georgia Monday morning.
"It's helping it's made a huge difference, but technology is not even, and it maybe never will be."
In January 2013, FEMA expanded the Wireless Emergency Alert System to include Amber Alerts in addition to weather emergencies and special notices from the President of the United States. The previous wireless system had only 700,000 registrants.
Unlike traditional emails and text messages, the WEA System automatically send notices to specific cell phone towers and access millions of people with no service delay.
Not all cell phones receive those messages, however.
According to the NCMEC, police activate Amber Alerts for specific cell phone towers to only reach specific geographic regions, to avoid overloading users with messages. In addition, cell carriers must comply with the new system, and cell phones must have wireless capability that's activated when the warning is issued.
"There was no mechanism for this 25 years ago, and now it has the speed of light behind it," says Howell. "This system has helped tremendously in just the past year."
According to the Florida Department of Law Enforcement, 10 Amber Alerts, including the alert for Onnika Fisher, have utilized the new system so far.
But Howell says, like technology, the program is still developing. He hopes Floridians will also sign up for traditional alerts to be sure they know when a young life is in danger.
"You may be the one who saved a child's life."
According to a non-profit dedicated to advancing the wireless industry called CTIA - The Wireless Association, most cell phone service providers are working to comply with the new system, and many new phones will be designed with wireless capability in future.
Cell phones users may contact their service providers to opt-out of weather and Amber Alerts, but by law cannot opt out of messages from the President.
To sign up for traditional Amber Alert notifications through the National Center for Missing and Exploited Children visit:
For more information about the Wireless Emergency Alert System and to find out if your cell phone is compatible, visit the CTIA - The Wireless Association page: http://www.ctia.org/your-wireless-life/consumer-tips/wireless-emergency-alerts/amber-alerts-via-wea