Joe LiebermanHomeland Security Chairman Sen. Joe Lieberman told Fox News' Chris Wallace that he wants the Department of Defense to launch an investigation into the shooting rampage at Ft. Hood. Lieberman said evidence indicates that Major Nidal Malik Hasan was probably a "self-radicalized, homegrown terrorist."

The New York Times reports, however, that investigators have tentatively concluded it was not part of a terrorist plot.

"If the reports that we're receiving of various statements he made, acts he took, are valid, he had turned to Islamist extremism, and, therefore, if that is true, the murder of these 13 people was a terrorist act and, in fact, it was the most destructive terrorist act to be committed on American soil since 9/11," Lieberman said Sunday.

According to this morning's New York Times, investigators have not ruled out the possibility Major Hassan "believed he was carrying out an extremist's suicide mission," but so far they have no evidence he was directed into violence or "ever traveled overseas to meet with extremist groups."

Lieberman wants the Department of Defense to conduct a special investigation to see if the shootings could have been predicted. "While the Army and the FBI are conducting the criminal investigation about exactly what happened and what Dr. Hasan should be charged with, the U.S. Army, the Department of Defense has a real obligation to convene an independent investigation to go back and look at whether warning signs were missed, both the stress he was under, but also the statements that he was making," he said.

Officials quoted by The New York Times say a continuing search of Hasan's computer has found email messages exchanged with ideologically radical Muslims, though there is no evidence he communicated with "known terrorists or anyone else who encouraged or helped him to orchestrate the shootings."

Lieberman told Fox, "The new face of terrorism in America would not just be the attacks as 9/11 organized abroad and sending people in here, it would be people within this country, homegrown terrorists, self-radicalized, often over the Internet, going to jihadist websites."

This video is from Fox's Fox News Sunday, broadcast Nov. 8, 2009.

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