WASHINGTON (CNN) -- It's been three days since Aaron Alexis went on a shooting rampage at the Navy Yard in Washington, killing 12. And each new day since has brought new revelations about his past.
As investigators sift through the evidence in the navy yard killings, navy officials say damage inside building 197 is so extensive it may take weeks to repair and reopen it. One official saying "There is blood everywhere, there is damage everywhere."
The mother of the gunman apologized Wednesday to the families of the victims saying, "I don't know why he did what he did and I'll never be able to ask him why. Aaron is now in a place where he can no longer do harm to anyone, and for that I am glad. To the families of the victims, I am so, so very sorry that this has happened. My heart is broken."
Investigators still don't know why. Law enforcement sources say nothing points to a specific motive for the rampage even after the seizure of Aaron Alexis' computer and other possessions and interviews with his social contacts for clues.
Yet, odd details are emerging. A federal law enforcement source tells CNN Alexis made unexplained etchings into the shotgun he used in the attack. The etchings read: "Better off this way" and "My elf weapon."
Investigators don't know what the sayings are supposed to mean. Still questions remain about whether the rampage could have been prevented.
Navy officials in Rhode Island never passed along police reports about Alexis' erratic behavior, claiming he was "hearing voices." Secretary of Defense Chuck Hagel says, "Where there are gaps we will close them. Where there are inadequacies we will address them. And where there are failures we will correct them. We owe the victims, their families and all our people nothing less."
New details have emerged suggesting authorities might have been able to contain the gunman more quickly. A government official tells CNN when the first radio call came in about a shooting at the Navy Yard, highly-trained tactical Capitol police officers attempting to help stop the rampage were told by a watch commander to stand down.
The Capitol police chief has ordered an "Independent Fact Review" of their response in the critical first moments after the shooting was reported.