JACKSONVILLE, North Carolina (CNN) -- The FBI suspects Marine Cpl. Cesar Laurean, sought in the slaying of a pregnant fellow Marine, has fled to his native Mexico, an FBI spokeswoman said Wednesday.
A warrant has been issued for Marine Cpl. Cesar Laurean, who's been charged with murder in Lauterbach's death.
"At this point in time we strongly suspect but have not confirmed that Laurean fled to Mexico," said Newsom Summerlin, FBI media representative in Charlotte, North Carolina.
Laurean, 21, is a native of Guadalajara, Mexico, and a naturalized citizen who lived in the Las Vegas, Nevada, area before joining the Marines.
The FBI said it is working with Mexican authorities to find and arrest Laurean if he is in Mexico.
Officials at the U.S. Embassy in Mexico City said a Spanish-language version of the FBI's wanted poster on Laurean was being developed Wednesday and would be posted on the embassy Web site. Watch friend talk about suspect, Lauterbach »
The officials are hoping local media outlets will pick up the poster and publish it. Anyone in Mexico with information is asked to contact the legal attache at the embassy, officials said.
On Tuesday, officials confirmed Laurean's Dodge pickup was at a motel near the Raleigh-Durham International Airport. Laurean had not checked into that motel, officials said. Watch motel employee talk about suspect's truck »
Laurean faces murder charges in the death of Lance Cpl. Maria Lauterbach, 20, who had accused Laurean of rape and who was eight months pregnant when she disappeared in December. Her charred body and a fetus were found buried Friday behind Laurean's house near Camp Lejeune, North Carolina.
Meanwhile, The Associated Press reported Wednesday that Laurean had sent letters to his wife, Christina Laurean, in North Carolina. The report, citing an unnamed law enforcement official, did not say when or where the letters were posted.
The Marine's wife gave authorities a letter Friday in which her husband allegedly wrote that Lauterbach had committed suicide in their home, and he buried the body in their backyard.
"So far, she has not given us any information that indicates he made contact with her," Sutherlin said of Christina Laurean.
Asked if authorities had obtained any other form of communication between the Laureans, he refused comment. There is the possibility that Laurean has planted false information to evade authorities and throw them off his trail, Sutherlin said, but would not elaborate.
Lauterbach last summer took out a protective order requiring Laurean to stay away from her, but Marine officials said Tuesday she told victims' advocates at Camp Lejeune that she didn't feel unsafe being around Laurean.
Laurean did not violate the military protective order, said Col. Gary Sokoloski, the judge advocate general officer for the II Marine Expeditionary Force.
Laurean continued to report for work on time in the weeks after Lauterbach's disappearance and denied having any kind of sexual contact with her, Sokoloski said.
Months earlier, Lauterbach had told superiors at Camp Lejeune, that Laurean had raped her.
However, "At no time did she indicate that she was threatened by Cpl. Laurean," Sokoloski said. "When she was asked if she felt threatened by Cpl. Laurean, she said she did not feel threatened."
She died from blunt trauma to the head, a prosecutor said Tuesday. Blood spatters were found in Laurean's home, police said. Watch motel employee talk about suspect's truck »
Marine officials said Tuesday that, until Lauterbach's remains were found, they believed she had left Camp Lejeune on her own accord.
On December 14, the day Lauterbach was last seen, her housemate, Sgt. Daniel Durham, found a handwritten note from her saying, "I could not take this Marine Corps life anymore so I'm going away. Sorry for the inconvenience. Maria."
The handwriting appeared to match Lauterbach's, Sokoloski said. Durham also noticed some of Lauterbach's personal items and her car were gone.
Durham called Lauterbach's sister regarding the note and reported her absence to the military, believing she had voluntarily gone "UA," for "unauthorized absence," said Lt. Col. Curtis Hill, a Marine Corps spokesman. See a timeline of the case »
Also that day, a surveillance camera showed Lauterbach withdrawing $700 from her bank ATM, and a one-way bus ticket to El Paso, Texas, was bought in her name for the next day. That ticket was never used, Hill said.
Military authorities did not know of the withdrawal, the ticket purchase, the withdrawal of another $400 from her account on December 24 by a man who covered the surveillance camera or the discovery of Lauterbach's cell phone lying alongside a Jacksonville highway until January 9.
When Lauterbach failed to show up for work December 17, the military was concerned, mainly because of the advanced state of her pregnancy, Hill said.
The Marines were attempting to have her listed as a deserter -- meaning federal authorities could be used to apprehend her -- to ensure she was receiving proper care, he said.
Military officials did not have contact with the Onslow County Sheriff's Office until December 27, after learning Lauterbach's mother had filed a missing persons report with them six days earlier, Hill said.
As part of the missing persons investigation, Laurean was interviewed on base by Onslow County authorities and the Naval Criminal Investigative Service. But he was interviewed as a possible witness, not a suspect, and was not detained, Hill said.
"At no point prior to Friday morning [January 11] ... did the regimental commander or the NCIS investigators feel that Lauterbach was anything other than UA or have information that Laurean was involved in any way," he said.
He noted that the military was not privy to several items of information until days afterward, but maintained the military was not trying to blame anyone else, saying it enjoyed a good relationship with Onslow County.
"There may have been a few hiccups here," Hill said. "We're going to work through that." E-mail to a friend
CNN's Rusty Dornin contributed to this report.