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Guns are wall-to-wall at the Guns Galore shop near Fort Hood, and so are posters: No Idiots Allowed. This Isn't a Place for Children to Play. Firearm Trafficking is Illegal.

But now that a second mass shooting at the Texas military base has been linked to guns bought at the squat brick store, which promises "3,000 Guns In Stock," the message Guns Galore clerks are emphasizing is don't blame them.

Fort Hood officials say Guns Galore, perched along the main road to the nation's largest Army post, is where Spc. Iván López bought the .45-caliber pistol used to kill three people and wound 16 others this week. It also sold a semi-automatic pistol, laser sights and high-capacity magazines in 2009 to Nidal Hasan, who then killed 13 people and wounded more than 30 others in a base rampage.

Lt. Gen. Mark Milley, the senior officer at Fort Hood, said López bought the gun on March 1, about a month before Wednesday's attack. Hasan also bought his FN 5.7 tactical pistol not long before his rampage in November 2009.

López turned the gun on himself after being confronted by police Wednesday. Before the attack, he was being treated for depression and anxiety while being evaluated for post-traumatic stress disorder. Milley said investigators believe López's unstable mental health condition may be an underlying cause of the shooting.

Greg Ebert, a longtime salesman at Guns Galore, said the store couldn't comment on López. But he bristled at anonymous angry callers and emails the store has been receiving, which he said included some asking if they're now happy more people are dead.

"We had nothing to do with what happened out here," said Ebert, emphasizing that he was speaking for himself and not the store. "If you want to blame somebody, go to the FBI and to the government at Fort Hood, and ask them why someone who was being psychologically evaluated wasn't flagged."

The 34-year-old truck driver from Puerto Rico seemed to have a clean record, but investigators are now pouring through López's personal history.

Federal law generally prohibits selling guns to people who've been involuntarily committed to a mental health facility or have been ruled by a court to be a danger to themselves or others. Gun control advocates say that leaves a gaping loophole during computer background checks.

Ladd Everitt, spokesman for the Coalition to Stop Gun Violence, called López's rampage another example of the gun industry profits taking precedence over safety. But he also cut Guns Galore a break.

"I can't possibly lay any blame at their door. Dealers are in this to make money," Everitt said. "So I don't think we should count on gun dealers to be psychiatrists or law enforcement officers. We need better laws on the books."

Business was steady at Guns Galore a day after the latest attack at Fort Hood.

Uniformed soldiers brushed past other customers between narrow rows of display cases packed tightly with handguns and old cellphones shot up by bullets. Long-barreled assault and hunting rifles stood on racks behind the main counter, where clerks in 2009 let Hasan videotape on his phone a lesson on how to reload, according to employees who testified in his trial last fall.

Guns Galore is about 2 miles outside Fort Hood, and it's the only place in the area other than pawn shops to buy firearms.

Ebert, a former police officer in Killeen, said the store counts local law enforcement agencies among its customers and said the store has a strong record complying with federal regulations.

Ebert also said he has turned away gun buyers before.

"We've refused to sell to a handful of people based on their mannerisms, their overhaul behavior — left you with the uncomfortable feeling that I'd rather not sell a firearm to this person," Ebert said.

Guns Galore is also where a soldier accused of planning to bomb Fort Hood troops at a restaurant in 2011 bought gunpowder and ammunition. The store later called police about Pfc. Naser Jason Abdo, saying they got a bad feeling about him, and Abdo was arrested the next day.

"I can only control what goes on inside this facility," Ebert said. "Once a person leaves a door, it's beyond me."

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