FORT WORTH, Texas (AP) — A medical examiner has ruled hypothermia as the cause of death for a Fort Worth woman and child whose unclothed bodies were found in a field about 200 yards from their wrecked car.

Police say the bodies of 27-year-old Lindsay Groce and 13-month-old Hailey Gardner were found Jan. 13 in a Fort Worth field. Their clothing was nearby.

The Tarrant County medical examiner's office said Thursday that Groce died of hypothermia with paradoxical undressing, which can occur in cases of severe hypothermia when the victim becomes disoriented, begins to feel hot and removes his or her clothing.

Their deaths were ruled accidental.

Homicide detectives have said there were no obvious signs of trauma and that it would be up to the medical examiner to determine how they died.