The Marine Corps said Wednesday it is cooperating fully with the Onslow County Sheriff's Office in the disappearance of Lance Corporal Maria Lauterbach, who is about eight months pregnant.

The sheriff's office has said Lauterbach's mother reported that her daughter was supposed to testify about an on-base incident.

"There are several findings and pieces of evidence that have been discovered that cause law enforcement to be concerned with the circumstances surrounding Maria's disappearance," the sheriff's department said in a statement.

Sheriff's investigators did not return calls seeking additional comment Wednesday, and it was not clear what Lauterbach was expected to say in testimony.

The State Bureau of Investigation also is working on the case. Marine Corps and U.S. Navy investigators are cooperating with the investigation, said First Lt. Richard Ulsh, a public affairs officer with the 2nd Marine Logistics Group.

Authorities say Lauterbach, originally from Dayton, Ohio, was reported missing Dec. 19 by her mother, who last spoke with her daughter on Dec. 13. Her cell phone was found Dec. 20 near the main gate at Camp Lejeune.

Lauterbach is assigned to the 2nd Marine Logistics Group of the II Marine Expeditionary Force. Camp Lejeune officials said she joined the Marine Corps in June 2006 and was trained as a personnel clerk.

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