The baby was in a women's restroom near the rental car counters.
About 9:30 Sunday night an employee found a newborn boy, but did not find his mother. Airport firefighters checked the baby before it was sent to a hospital.
Surveillance videos released by authorities shows a woman apparently arriving from a flight, then walking with a covered bundle toward the bathroom, where she dropped off the infant at a changing table inside the women's restroom.
She left a note with the baby. It read:
The woman who dropped off the baby is believed to be in her 20s, between 5-5 and 5-7 with dark hair. She wore a crochet beanie, a dark jacket, dark yoga pants, a backpack and a purple neck pillow.
The child was transported to the hospital for care.
Police found items in the women's bathroom trash can -- including a white camisole, a green pair of lace underwear and a black pair of sweat pants, all with blood and bodily fluids -- that possibly belonged to the woman.
The baby is in the custody of the Arizona Department of Child Safety.
If you have any information on who this woman is - you are asked to call police.