The posts will show up in both mobile and desktop feeds, and will not trigger a notification. Facebook said it will be careful to deploy the alerts only in time-sensitive, practical situations -- when it can do the most good -- and that the average user will rarely see an AMBER alert.
"We would never want someone to see this and say, 'Oh, another one of those,'" said Emily Vacher, who works on the social network's trust and safety team. "We really want people to know these are rare so that they'll take notice and know they're in a position to help."
Ideally, of course, Facebook will never have to use the program. But in the event that someone abducts a child, the network hopes it can become the "world's largest neighborhood watch," said Vacher.
Facebook doesn't have a hard and fast rule about who will see the alerts in every case. That will vary based on where the abductions take place. Vacher, who worked with the FBI before coming to Facebook, said that the network is more concerned with "quality over quantity" when it comes to who sees the alerts.
The social network will look at users' location information to decide who will get the alerts. For example, Vacher said, if someone checks-in at the Empire State Building while on vacation, they may then get an alert for a child abducted in Manhattan.
The program formalizes what some users have already been doing on Facebook, she said. In many cases, people are already sharing information on missing children or missing persons online -- and found the people they were looking for.
"This has resulted in kids coming home," Vacher said of the organic movement. "We're just looking at how we can amplify that."
The Department of Justice hailed the partnership with Facebook -- as well as one with Microsoft’s Bing search engine that includes AMBER alerts in search results.
“Each of us can help by paying close attention to alerts that come in – and by making sure you are plugged into the AMBER Alert network via social media,” said Attorney General Eric Holder in a statement.