The Journal News -- GREENBURGH — As she finalized plans for her son's funeral yesterday, Sonia LaSanta was still searching for information on his death, which remains a mystery.

The military has revealed little since Marine Lance Cpl. Efrain Sanchez Jr. died Sunday at Camp Blue Diamond in the western Iraqi city of Ramadi.

The Department of Defense announced that Sanchez, 26, died as the result of a nonhostile incident, but military officials say the circumstances remain under investigation.

"They're just telling me they're investigating. That's it," a frustrated LaSanta said yesterday in a telephone interview.

LaSanta, a Greenburgh resident, said she was told that her son took a gunshot wound to the head, but several calls to military officials have yielded no additional information.

A Defense Department spokesman, 2nd Lt. Shawn Mercer, said the investigation could take days or months. He could not describe the investigation process or confirm that Sanchez died of a gunshot wound.

"All I know is that the incident is under investigation," Mercer said.

Yesterday, Sanchez's wife, Janice, arrived from North Carolina, where her husband was based at Camp Lejeune. Sanchez was assigned to Headquarters Battalion, 2nd Marine Division, II Marine Expeditionary Force. His unit arrived in Iraq in stages in February and March.

Sanchez lived in Port Chester before joining the Marines in February 2004.

Before that, he and his identical twin brother, Nicholas, had lived in Westchester, Pennsylvania and the Bronx.

The boys spent their childhoods in Brooklyn, where Sanchez will be buried in the same cemetery as Virginia Sanchez, his grandmother.

Before he left for Iraq, Sanchez asked to be laid to rest beside her at Cypress Hills Cemetery if something were to happen to him.

A wake for Sanchez will be held from 6 to 9 p.m. today and from 2 to 4 and 6 to 9 p.m. tomorrow at Grace Funeral Chapel, 607 N. Conduit Blvd., Brooklyn. The funeral will be at 10 a.m. Saturday at Grace Funeral Chapel.