Tucson Airport Authority officials released surveillance video that purportedly shows the mother of the child, seen walking through the airport holding something wrapped in blue fabric.
Authorities developed this timeline based on the amount of blood found inside a toilet stall and on some items of clothing found stashed inside a rubbish bin in the first bathroom.
Airport police are looking for a woman who they say may have given birth and left her baby in an airport restroom with a note asking authorities to find him a good home.
The child was found with a handwritten note, which mentioned the woman wanting a better life for her baby. It continues: "I just want what is best for him and it's not me".
Arizona is a "safe haven" state, meaning parents can drop off newborns at designated locations like hospitals and churches if they are unable to care for them.
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The woman in this CCTV footage arrived at the Tuscon International Airport as an expectant mother, but walked out alone. The custodian also found bloody clothes in a trash can.
The child was in good condition, authorities said.
According to an airport spokeswoman, the baby appears to be healthy and is now in the custody of the Arizona Department of Child Safety.
The note then switches to what appears to be a plea and apology from the mother. When she asked the woman if she was okay, the suspected mother would only say that the baby was 3 months old and left in a hurry.
But since an airport is not a designated location, the woman could face criminal charges. "We would like to know who she is, but we've exhausted our resources", an airport spokesperson tells the Star.