The man accused of walking into a King Soopers grocery store in Boulder, Colo., on Monday and killing 10 people was armed with a military-style semiautomatic rifle and a pistol, law enforcement officials said.
Statements from the police and the charging documents did not make it clear which of the weapons was used in the attack, but it appeared at least one is a semiautomatic derivative of the assault rifles that have long been used by the American military.
According to a police affidavit, the suspect charged with 10 counts of murder, Ahmad Al Aliwi Alissa, bought a Ruger AR-556 semiautomatic weapon, essentially a shortened version of an AR-15 style rifle marketed as a pistol, six days before the killings took place. It is also unclear if that weapon was used in the shooting on Monday.
Both the AR-15 style rifle and the Ruger version fire the same small-caliber, high-velocity ammunition, which was first developed for battlefield use.
Under Colorado law, a handgun is defined as a “pistol, revolver or other firearm of any description, loaded or unloaded, from which any shot, bullet or other missile can be discharged, the length of the barrel of which, not including any revolving, detachable or magazine breech, does not exceed 12 inches.”
Based on their size, “AR pistols” are much easier to conceal than a typical AR-15 carbine or rifle. According to the manufacturer’s website, the Ruger AR-556 pistol comes with either a 9.5-inch or 10.5 inch-long barrel, while a typical AR-15 has at least a 16-inch barrel.
Some retailers in Colorado sell a version of the Ruger AR-556 with a magazine that holds fewer than 15 rounds to comply with state codes, The Denver Post reported.