A woman accused of abandoning three newborn babies - one of whom died of exposure in the back of a pickup truck - pleaded not guilty Wednesday to murder and child-abuse charges. Nancy Ortiz, 22, of Orosi, entered her plea to one count of murder and three counts of child abuse. She has been held without bail at a Tulare County jail since her arrest Monday. Authorities believe Ortiz left her newborn daughter to die in the bed of a pickup truck in December, after also abandoning the baby's two older siblings as infants in her neighborhood. The first two babies were found alive and have been placed with families.

Sheriff's Department officials say DNA tests proved Ortiz gave birth to the dead baby, who authorities named Angelita DeOrosi, or Orosi's little angel. Officials have said there's an "extremely high probability" that tests will confirm she also was the mother of the other deserted newborns.

Detectives determined Ortiz was a suspect in the case when they interviewed her after neighbors spotted her 3-year-old daughter walking naked on the street a quarter-mile from home. Prosecutors have filed a child neglect charge for that incident and placed the toddler and her 4-year-old brother in protective custody.

Ortiz's family members and friends attended the hearing Wednesday and appeared teary at seeing her in an orange- and white-striped jail suit.

Ortiz was scheduled to appear next in court on Aug. 8 for a preliminary hearing conference.