Fort Hood, Texas (CNN) -- Maj. Nidal Hasan has been charged with 13 preliminary counts of premeditated murder stemming from last week's shooting at Fort Hood Army Post, an Army investigator said Thursday.
Army Criminal Investigation Command spokesman Chris Grey said the investigation continues and Hasan, 39, may face additional charges at court-martial.
He said Hasan remains hospitalized from gunshot wounds he received from two police officers who responded to the November 5 shooting.
Hasan is accused of killing 13 people -- a dozen soldiers and a civilian -- at the post's processing center, where soldiers were preparing to deploy to Afghanistan and Iraq.
Dozens others were wounded, and 12 remain hospitalized, Col. John Rossi said Thursday.
The FBI has said that its investigations indicate the "alleged gunman acted alone and was not part of a broader terrorist plot."
Hasan's civilian attorney, retired Army Col. John Galligan, said that he has spoken with his client, but that Hasan was heavily sedated.
"I think the closest thing that indicates that there's a court-martial in the works is last night ... I did receive an e-mail from the prosecutor at Fort Hood indicating to me that the pass privileges and leave privileges of Maj. Hasan had been revoked," Galligan said.