Camp Lejeune, N.C. — A pregnant Marine who disappeared three weeks ago from Camp Lejeune is due to deliver any day, and authorities grow more concerned daily about her safety.

Lance Cpl. Maria Lauterbach 20, was reported missing by her mother on Dec. 19, five days after the two last spoke, authorities said. Her car was found Monday night at a bus station near base – investigators said it hadn't been there long – and they found her cell phone on N.C. Highway 24.

The Marine Corps Times newspaper has reported suspicious activity has been flagged in Lauterbach's bank accounts since her disappearance.

"The more that we have suspicious things come up, the more concern we have that something is not right with this lady's disappearance," Onslow County Sheriff Ed Brown said.

The Onslow County Sheriff's Office is working on the case with the State Bureau of Investigation and the Naval Criminal Investigative Service.

Lauterbach, a member of the 2nd Marine Logistics Group, joined the Marines in June 2006 but hasn't been deployed. She was 8½ months pregnant when she was last seen and could already be past her due date.

"It does become more of a concern for endurance when you're dealing with a lady who is near delivery with child," Brown said.

Investigators declined to discuss a possible "significant other" or the father of Lauterbach's baby.

She lived in the Midway Park housing area, which isn't on base but is reserved for Marines. Deputies have searched the home and questioned some roommates.

Investigators are still waiting to talk with at least one male roommate who might be deployed, Brown said, adding the man could be considered a person of interest.

"Until you can interview him and eliminate him, you still consider them as key people of concern," he said.

Lauterbach also was scheduled to testify in a criminal case after being the victim of an on-base crime, he said, declining to elaborate.

"The longer it goes, the more stressful it gets that something may have happened to this lady against her will," he said.

Lauterbach's mother came to Onslow County last weekend from the family's home in Montgomery, Ohio, to provide whatever assistance she could in the investigation. Friends and relatives also set up a Facebook.com page to help find the missing Marine, who they said would never go anywhere without letting someone know.

"We're going to turn over every stone trying to locate her," Brown said.