Karla Elizabeth Serna Davila was 18 when she last contacted her family on December 12, 2011, saying she was in Nogales, Mexico and planned to cross into Nogales, Arizona the next day. Described as Hispanic with long, straight black hair and brown eyes, her reported height ranged from 5 feet 3 inches to 5 feet 8 inches and her weight from 145 to 155 pounds. Distinguishing marks included pierced ears, a scar on her upper right eyebrow, and a mole on the lower right side of her chin.

When last heard from she was believed to be wearing a brown and yellow cotton shirt, gray cotton pants, and a gray cotton sweater. The disappearance was reported on December 29, 2011, and the Pima County Medical Examiner’s Office in Tucson is handling the investigation.

Few concrete details are available about what happened after that final call from Nogales — does anyone have information about Karla’s movements around December 12–15, 2011?