(WJLA) - The owners of United Gun Shop in Rockville confirmed to ABC7 News that they sold the Mossberg 500 shotgun used in the Columbia Mall shooting to 19-year-old Darion Aguilar on Dec. 10.
"Nothing about him was sketchy," said Cory Brown, co-owner of United Gun Shop. "There were no red flags."
In fact, the store owners described the teen suspected of killing two people Saturday morning as very polite and said he appeared to be in a good mood, smiling as he talked with the owners.
Per federal law, Aguilar filled out Firearms Transaction form known as a 4473 and was then checked against an FBI database. Brown says Aguilar "received an instant proceed within one minute," and then paid cash for the shotgun, which sells for about $430.
Federal gun laws allow people 18 and over to purchase long guns and shotguns upon passing a background check, but you must be 21 to buy a handgun or assault-style rifle after a similar check and required multi-day waiting period. Maryland mandates a 7-day waiting period for handguns.
Last year Maryland tightened its gun laws, banning the sale of assault-style weapons, high capacity magazines and by requiring additional handgun training before a weapon can be purchased. The new laws did not address shotgun sales.
"There are a lot of things about the gun law I think we should look at again, that would be one," said Democratic State Sen. Brian Frosh from Montgomery County, a major backer of Maryland's new gun control measures and candidate for Maryland Attorney General.
"I would like us to do whatever we can," said State Sen. Jamie Raskin, also a Democrat representing Montgomery County and a supporter of the new law, who agrees there's an age requirement loophole in the law when it comes to shotguns."
The owners of the United Gun Shop are still trying to reconcile the customer they encountered with the horrible acts of violence committed over the weekend.
"He didn't ask any questions that were off base," Brown and his business partner Dan Millen told ABC7 News Reporter Kris Van Cleave. The owners say Aguilar told them he was concerned about home protection and asked several questions about safety.
Aguilar also purchased two boxes of ammunition, one box of "home defense" shells, often referred to as buckshot, and one box of bird shells. Around Christmas, he returned to the gun store to buy another box of bird shells, telling the owners he'd been practicing.
Brown says ATF agents called him at home around 3 p.m. Saturday asking for help identifying the owner of the weapon used in the mall shooting earlier that morning. When the serial number came back to the shotgun Aguilar purchased, Brown says his initial reaction was that someone must have taken the gun from the suspect and used it.
"I have no idea why he would do this," Brown said.