Investigators continue to look for answers this morning following Thursday's massacre Fort Hood, Texas...the nation's largest Army post.

The shooting left at least 13 people dead and dozens more wounded.

Investigators say that shooter was Major Nidal Malik Hasan, a 39-year old Army psychiatrist recently promoted from Captain and transferred to the Texas post just four months ago.

Base commanders say they had no problems with Major Hasan before his shooting rampage.

Investigators say the horrific attack could have been much worse if not for the actions of civilian police officers who responded.

Officials say perhaps no one did that better than police officer Kimberly Munley.

"Officer Munley showed up, and initial indications are, very quickly met and had a confrontation with him," said Colonel John Rossi.  "Both exchanged fire and both were wounded in that exchange."

She is in stable condition following overnight surgery.

Today has been designated as a day of mourning at Fort Hood.

Officials are still notifying next of kin of those killed and injured and also working to help survivors on the Army post deal with the mental scars from the attack.

Ironically it's a mission that would have been assigned to the soldier inflicting the pain so many are being forced to deal with here.

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