Three victims and the gunman are dead following a shooting at the Fort Hood Army post Wednesday, NBC News is reporting. One other victim is in grave condition, while at least 11 others are injured, according to NBC News.

A military official told NBC News that the deceased shooter, identified as 34-year-old enlisted Army soldier Ivan Lopez, appeared to be the only shooter despite an earlier report of two gunmen. NBC News reported that the shooter was in uniform, and that the shooting may have resulted from an argument in the motor pool.

The Associated Press, citing an internal memo from the Justice Department, reported that the Fort Hood shooter died of a self-inflicted gunshot wound.

The names of the victims have not yet been revealed.

Scott & White Hospital in Temple confirms they have a command center in place and have received three patients from the post.