JACKSONVILLE , North Carolina -LRB- CNN -RRB- -- Christina Laurean has told authorities she was attending a Christmas party on the night her husband allegedly killed pregnant Marine Lance Cpl. Maria Lauterbach , according to police . Marine Cpl. Cesar Laurean , wanted for murder , may have fled to his native Mexico . Marine Cpl. Cesar Laurean is charged with first-degree murder . He remains at large , and authorities say he may have fled to Mexico . Also , an affidavit obtained Thursday by CNN states that Christina Laurean knew about the death one day before reporting it to authorities . The Marines were assigned to Camp Lejeune , North Carolina . Lance Cpl. Maria Lauterbach was eight months pregnant when she was reported missing December 19 . Authorities say she was killed four days earlier . A warrant allowed authorities to search Western Union records . Authorities said in the accompanying affidavit that Cesar Laurean and his wife received a transfer of money between December 10 and January 12 . The affidavit provided no other details . Authorities requested the search warrant and all accompanying documents be sealed . The FBI says Laurean may have fled to his native country of Mexico . Cesar Laurean , 21 , is a naturalized U.S. citizen . He mailed at least one letter from Houston , Texas , since his disappearance , CNN affiliate KPRC in Houston reported Thursday . According to the affidavit , Christina Laurean , 25 -- who also is a Marine -- went with her husband to a Jacksonville attorney on January 10 , and the lawyer told Cesar Laurean he could face the death penalty . The next day , Christina Laurean reported Lauterbach 's death to the Onslow County Sheriff 's Office , where she appeared with an attorney and a sergeant from her former chain of command . She turned over to deputies several notes from her husband that she said she found at their home . In the notes , Cesar Laurean said Lauterbach committed suicide and he buried her . Lauterbach , 20 , had accused Cesar Laurean of raping her and was to testify at a military hearing not long after her disappearance . According to a co-worker , she feared Cesar Laurean , although the military said she told prosecutors she did not . Lauterbach 's allegations involved two encounters -- one on or about March 26 and one approximately two weeks later , the Marines told CNN . Lauterbach received two protective orders , one of which was in effect when she died . Christina Laurean on January 11 told authorities her husband had denied the rape allegations and said he was not the baby 's father , according to the affidavit . In the document she says her husband told her : Dubois contends the facts show probable cause exists to show that Cesar Laurean `` committed murder . '' The detective said he does n't believe Lauterbach committed suicide , especially because she had told people she wanted the child . Christina Laurean told police she was at a Christmas party for her husband 's Marine unit during the late afternoon and evening of December 15 , Onslow County Sheriff Ed Brown told CNN . Her husband did not attend the party , she told authorities . Lauterbach 's charred remains and those believed to be of her unborn child were found in a fire pit in the Laureans ' backyard . Police have said blood spatters were found throughout the Laurean home on walls and ceilings , and evidence showed someone tried to clean them up and paint over them . DNA testing is being conducted to see if Lauterbach 's unborn baby was fathered by Cesar Laurean , Brown said , adding there was no rush on the part of detectives to get those results . The FBI is offering a $ 25,000 reward for information leading to Cesar Laurean 's arrest . Anyone in Mexico with information is asked to contact the legal attache at the U.S. Embassy in Mexico City . Meanwhile , authorities have discovered the weapon likely used to kill Lauterbach , a spokesman for the Onslow County Sheriff 's Office said Thursday . Authorities have said the woman died of blunt force trauma to the head . A man who had rented a room to Lauterbach , Sgt. Daniel Durham , told investigators he found a note from her December 14 -- the day she was last seen -- saying she was tired of the Marine Corps life and was leaving . E-mail to a friend CNN 's Rusty Dornin contributed to this report .