McHugh did not name the dead gunman. | John Shinkle/POLITICO Army: Shooter new to Fort Hood

The Army confirmed on Thursday the Fort Hood gunman who killed three other soldiers was a 34-year-old Army truck driver, originally from Puerto Rico, who had recently transferred to the base from another post in Texas.

Spc. Ivan Lopez was assigned to the 49th Transportation Movement Control Battalion of the 13th Sustainment Brigade, Lt. Gen. Mark Milley, the commanding general at Fort Hood, said during an afternoon news conference. Lopez reported to the base in February after several years at Fort Bliss, Texas, Milley said, although he did not come to seek treatment at its Warrior Transition Unit.


Milley did say, however, he believed “we have very strong evidence” that Lopez had an unstable psychological condition.

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Army records released Thursday showed Lopez deployed twice, once to Egypt from January 2007 to January of 2008 and once to Iraq from August of 2011 to December of that year. Lopez joined the service as an infantryman, was for a time a National Guard drummer and, most recently, had moved into the transportation military occupational specialty.

Milley said investigators are interviewing soldiers and others who witnessed Wednesday’s rampage and was not prepared to discuss what might have prompted Lopez to go on his shooting spree.

Asked about reports that Lopez might have gotten into an “altercation” with another soldier, Millie said, “There’s a strong possibility [of] that immediately proceeded the shooting, but we do not have definitive confirmation of that.”

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Milley also would not comment on reports that Lopez might have been angry because the Army would not let him take more time to attend his mother’s funeral.

The Army will look at everything it can as it looks into what happened, the general said.

Army Secretary John McHugh said earlier on Capitol Hill that a background check showed the soldier, who killed three people and himself, had “no involvement with extremist organizations of any kind” but that “possible extremist involvement” was still being investigated.

“We’re going to keep an open mind and an open investigation,” McHugh told the Senate Armed Services Committee on Thursday at the top of a hearing on the Army’s budget request for the next fiscal year. “The circumstances remain very fluid.”

McHugh said the man the Army later identified as Lopez was under medical treatment and had been prescribed several medications, including the sleep aid Ambien. He was in the process of being potentially diagnosed with post-traumatic stress disorder, but none of his doctors saw any warning signs in his most recent visits.

“The plan forward was to just continue to monitor and treat him as deemed appropriate,” McHugh said.

He also explained that the shooter’s weapon was a .45-caliber pistol that had recently been purchased and that the shooter lived off-post. The weapon doesn’t appear to have been registered with base officials. “We try to do everything we can to get soldiers to register their personal weapons,” McHugh added, noting that the Army can’t legally compel registration for soldiers living off-post — but that bringing the weapon onto the base wasn’t allowed.