RAPID CITY, S.D. — Authorities in western South Dakota say the search for a missing 9-year-old girl is turning into an effort to find her body.

The Pennington County Sheriff's Office said Tuesday night that if the girl was outside, it's unlikely she survived. The girl ran away from a residential youth home amid frigid weather.

Investigators say the girl wasn't wearing a coat when she slipped away from the Children's Home Society on Sunday morning near Rapid City. The temperature in the area was about 29 degrees (negative 1.7 Celsius) at the time.

Authorities have not ruled out the possibility that she found a warm place or that someone picked her up. More than 200 people assisted by dogs have been searching for the girl over the last three days.