The search for a U.S. Marine's pregnant wife who went missing nearly two weeks ago as she was headed to Joshua Tree National Park is expected to intensify over the weekend, officials said.
Search and rescue crews have been scouring the massive national park ever since 19-year-old Erin Corwin of Twentynine Palms was reported missing on June 29.
Authorities hope the investigation will intensify over the weekend as they expect more volunteers will help with search efforts.
Although San Bernardino County sheriff's officials aren't saying her disappearance is the result of foul play, they believe it is suspicious and homicide detectives are investigating the case.
"It is suspicious that a young woman, who's pregnant, is missing for so many days," sheriff's spokeswoman Cindy Bachman said.
Little information has been released about her disappearance.
The last major development was nearly two weeks ago after her car was found June 30 near the U.S. Marine Corps Air Ground Combat Center in Twentynine Palms.
Corwin, who is three months pregnant, was last seen about 7 a.m. June 28 leaving her home at the military base and heading toward the national park.
She had planned to search the park for areas to visit when her mother, Lore Heavilin, came into town, CBS 8 reported. But when she did not return, her husband, Lance Corporal Jonathan Corwin, reported her missing the following day.
Her phone has been either dead or turned off since that time, according to the Locate Erin Facebook page created by her family after her disappearance.
Her mother told KESQ-TV she had planned to make a trip from Tennessee to Twentynine Palms for Corwin's birthday on July 15.
Detectives have interviewed her husband and family as part of their investigation into her disappearance.
"Everybody has been cooperative," Bachman said.
The couple was originally from Oak Ridge in Tennessee, according to a Go Fund Me page created to raise funds for a reward for any information about her disappearance.