The San Bernardino County Sheriff's Department continues its investigation into the disappearance of Erin Corwin, but officials said the incident has not been classified as a criminal investigation at this time.
Deputies aren't releasing any information regarding possible witnesses, witness statements or investigative techniques during the search.
Specialized investigators have been in Twentynine Palms and in and around Joshua Tree National Park searching and flying through the remote areas.
Officials said the ground search will continue throughout the weekend.
The sheriff's department plans to provide updates as new information becomes available.
Anyone who may have information regarding the whereabouts of Erin Corwin is asked to contact the Specialized Investigation Division at (909) 387-3589.
Callers who want to remain anonymous can also call the We Tip Hotline at 1-800-782-7463.
Continue to follow News Channel 3 and CBS Local 2 on air and online as more information is released.