Smartphone Emergency Alert Startles SoCal

Phones across the Golden State buzzed, beeped and whirred Monday night as California sent out its first statewide Amber Alert to mobile devices.

The message -- accompanied by what some have called a "screeching" tone -- startled many smartphone users unfamiliar with the urgent-sounding notifications.

"It’s loud. It’s meant to get people's attention," said Brian Josef, assistant vice president regulatory affairs at CTIA-The Wireless Association. "We can understand the surprise of people, but I think the response overwhelmingly has been, 'Wow, this is a good service.'"

Wireless Emergency Alerts were first introduced in 2012, and are meant to be used sparingly so as not to create what Josef called a "car-alarm syndrome," in which users tune out the warnings.

There are three kinds of emergency alerts, according to CTIA, which represents carriers:

• Presidential Alerts issued by the commander in chief during a national emergency;
• Imminent Threat Alerts that warn of severe man-made or natural disasters, such as hurricanes, earthquakes, tornadoes, etc.; and
• Amber Alerts that meet the U.S. Department of Justice's criteria to help law enforcement search for an abducted child.

The alert program was created by the Federal Communications Commission (FCC) and Federal Emergency Management Agency (FEMA), and executed by CTIA-The Wireless Association. And is executed by wireless carriers on a voluntary basis.

Law enforcement and government officials are responsible for sending the alerts.

Monday night's notice was activated by the California Highway Patrol's Emergency Notification and Tactical Alert Center, according to the a news release.

It was related to the abduction of a 16-year-old girl and her 8-year-old brother, pictured below. The children’s mother and another child were found dead inside a burned home near the California-Mexico border Sunday night.

The message described a car the suspect -- James Lee Dimaggio -- is believed to be driving: a blue Nissan Versa with California license plate 6WCU986.

There’s no fee to receive the text-like messages. Users can opt out of Amber and Imminent Threat alerts, but cannot opt out of Presidential Alerts, according to FEMA.

iPhone users can go into their Settings app, select Notifications and scroll to the bottom of the page to turn off "government alerts."

If you didn’t receive a notice Tuesday night, officials say you likely need to upgrade your phone’s software. Consumers should contact their provider with any questions about opting out.

The alerts are location-based and beamed from local cell towers to mobile devices in the area. That means even if your phone is registered in, say, Connecticut, but you’re in Southern California, you would have received Tuesday night’s alert.

Most cellphone users -- 97 percent of American customers -- subscribe to wireless providers that offer the alerts, according to CTIA.

And with so many mobile users able to get the alerts, there was plenty of chatter about the notifications, as seen in the Storify below:

[View the story "Amber Alert Startles SoCal Awake" on Storify]