THE MASSACRE AT FORT HOOD…. In the immediate aftermath of the shooting rampage at Fort Hood, there were a variety of reports that proved to be inaccurate. Here’s what we know, as of this morning.

An Army psychiatrist facing deployment to one of America’s war zones killed 13 people and wounded 30 others on Thursday in a shooting rampage with two handguns at the sprawling Fort Hood Army post in central Texas, military officials said.

It was one of the worst mass shootings ever at a military base in the United States.

The gunman, who was still alive after being shot four times, was identified by law enforcement authorities as Maj. Nidal Malik Hasan, 39, who had been in the service since 1995. Major Hasan was about to be deployed to Iraq or Afghanistan, said Senator Kay Bailey Hutchison, Republican of Texas.

Clad in a military uniform and firing an automatic pistol and another weapon, Major Hasan, a balding, chubby-faced man with heavy eyebrows, sprayed bullets inside a crowded medical processing center for soldiers returning from or about to be sent overseas, military officials said.

The victims, nearly all military personnel but including two civilians, were cut down in clusters, the officials said.

Hasan was shot by a first-responder, who was herself wounded in the exchange. While initial reports said both were killed, it now appears both Hasan and the first-responder who shot him survived.

Hasan was described as the sole gunman in the shooting rampage, and has been hospitalized off base, under around-the-clock guard.

While words like “al Qaeda” and “terrorism” were quickly thrown into the media mix, Army Lt. Gen. Robert Cone, who briefed reporters on the shooting, said the preliminary evidence did not suggest that the rampage had been an act of terrorism.

There were also reports about multiple shooters. It appears that three other soldiers were taken into custody, but their roles in the incident are unclear. While a local congressman said they were later released, the Army did not confirm this.

Attention now turns, of course, to Hasan, who he is, and what motivated him to attack. Based on what we’ve learned, Hasan is a Virginia-born doctor who once practiced at Walter Reed Army Medical Center. He graduated from Virginia Tech in 1997 and earned a doctorate in psychiatry from the Uniformed Services University of the Health Sciences in Bethesda.

There were some reports suggesting he is a recent convert to Islam, but additional reporting suggests he is a life-long Muslim, with no history of violence or radicalism. By one account, Hasan reconsidered a military career after having been “harassed” by other soldiers about his faith, though we don’t know if that had anything to do with the shooting.

In terms of motivation, one of the common threads this morning points to Hasan’s unwillingness to deploy to Iraq or Afghanistan, after having counseled returning soldiers with post-traumatic stress disorder.

There will be an extensive investigation and we’ll no doubt know more in the coming days and weeks.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.