Why was there an emergency/amber alert 4/13/13 at 4am

No one here would know. Ask whoever put the alert out.

Because I was reported missing.

Check local news sites in your city. One of them may report on a missing child report.

Templeton Peck wrote:

Because I was reported missing.

Glad you've been found!

Amber alerts are not included in iPhone or iOS features. If you get them, it's originating either from a 3rd party app or y our cell carrier. Contact whoever is sending them out.

Settings>Notifications>Government Alerts...you can turn on/off here.

"Government alerts" are issued via the carrier and vary from carrier to carrier, region to region.

Show government alerts in Notification Center: Choose the alerts you want to see from the Government Alerts list. Government alerts are not available in all areas, vary by carrier and iPhone model, and may not work under all conditions. For example, in the United States, iPhone 4S or later can receive presidential alerts and you can turn AMBER and Emergency Alerts (which includes both Severe and Extreme Imminent Threat alerts) on or off. In Japan, iPhone 4 or later can receive Emergency Earthquake Alerts from the Japan Meteorological Agency.

modular747 wrote:

Amber alerts are not included in iPhone or iOS features. If you get them, it's originating either from a 3rd party app or y our cell carrier. Contact whoever is sending them out.

Yes, they are, if you have Verizon, at least. AT&T doesn't support them last I checked. See wjosten's directions. They are also mentioned in the passage you quoted. But, no, neither Apple nor the iPhone are responsible for the content, of course.

No, they are provided by the carrier, not the iOS or Apple, which is why there are no AT&T government alert options. The point here is that only the carrier determines what and when gov. alerts are delivered.

My Verizon iPhone 5 has

Settings > Notifications > Government Alerts

There are two alerts listed that I can turn on or off individually. They are Amber Alerts and Emergency Alerts.

I have Amber Alerts set to off and Emergency Alerts set to On. I've never received an Emergency Alert yet though.

modular747 wrote:

No, they are provided by the carrier, not the iOS or Apple, which is why there are no AT&T government alert options. The point here is that only the carrier determines what and when gov. alerts are delivered.

I think we may be saying the same thing in slightly different ways. The only way you can get the Amber Alert on the phone is if you have it turned on in the iPhone settings. This emergency alert/amber alert system will eventually be enabled in all phones, as I understand it (wjosten or deggie probably knows the answer to that better than I), just like E911 abilities. The government sends out the alerts. The carrier implements the ability to send them out. The phone manufacturer makes the phones able to receive them. AT&T hasn't implemented the ability on their network yet.

And, in case anyone cares, there's actualy a third type of alert, a Presidential Alert. There is no option to turn those off, however. If your phone is capable of receiving government alerts, it will get them.

Participation by carriers, while occurring, is voluntary. Alerts by the President cannot be blocked or turned off.