The main criteria is proof that a child 17 years of age or younger was in fact abducted.
Since Crosbyton authorities know 2-year-old Leah Marie Aguirre was taken by a Hispanic man posing as a CPS case worker, the move to issue an Amber Alert met the guidelines.
According to law enforcement in order to issue a nationwide Amber Alert there are criteria's that must all be met.
Including confirmation that the child was abduction, meaning witnesses are vital in the process.
The child must be believed to be in imminent danger, by being at risk of serious bodily injury, harm or death
Authorities must have sufficient descriptions.
Crosbyton authorities were able to describe baby Leah as being 2-years-old, black hair, brown eyes and about 30 pounds.
The man posing as the CPS worker was a Hispanic man going by the name of Miguel, slender build, in his late 40's to early 50's and standing about 5' 4'' to 5' 6''.
The two were last seen leaving Crosbyton in a red car, similar to a red Ford Focus.
The FBI is heading the investigation along with Crosbyton authorities, the Texas Rangers and Missing and Exploited Children.
All agencies are working together in this nationwide search for baby Leah.
"The investigation to date is working to interview individuals that are connected to Leah and we are also following tips and leads by the public," said Katherine Chaumont, with the FBI, "the publics assistance has been great the more specific the info the better."
They are asking for your help as well if you have any information call the FBI AT 972-559-5000.