(NEW YORK) -- Adam Lanza, who carried out a massacre of children at Sandy Hook Elementary School in Newtown, Conn. last year, had accumulated an arsenal that included pistols, rifles, revolvers, shotguns, hatchets, knives and other "cutting instruments," according to search warrants released on Thursday.
The documents also stated that Lanza's deadly rampage took no longer than five minutes from the time Lanza forced his way into the school to when he turned a gun on himself.
Five previously sealed search warrants were released Thursday for Lanza's home, which he shared with his mother Nancy Lanza, and his car. Nancy, 52, was the first victim of her son's shooting spree. The documents represent the fullest picture yet of the shooting.
On Dec. 14, Adam, 20, went to Sandy Hook Elementary School, where he shot his way into the building and killed 20 children and six adults with a Bushmaster .223 caliber model XM15 rifle. The Bushmaster was loaded with a 30-round capacity magazine. Fourteen rounds were in the magazine when the Bushmaster was recovered by police. There was one round in the chamber.
Adam took his own life with a single shot from a Glock 10 mm handgun. He also had a loaded 9mm Sig Sauer P226 handgun with him. Additionally, he had three magazines for the Bushmaster, each containing 30 rounds, and additional ammo for the handguns.
When the carnage was over, police counted 154 spent bullet casings.
The warrants also say police found computers and gaming devices.
The FBI interviewed a "citizen witness," whose name is redacted in the documents, who said Adam "rarely leaves his home." The person said Adam was "a shut in and an avid gamer who plays Call of Duty, amongst other games."
There were also books that included Look Me in the Eye – My life with Aspergers, Born on a Blue Day – Inside the Mind of an Autistic Savant, and NRA Guide to the Basics of Pistol Shooting.
Police recovered the National Rifle Association certificates of both Nancy and Adam Lanza. Adam's was found in a duffel bag that also contained 50 rounds for a .22 caliber rifle and other ammo, ear protection, eye protection, binoculars and numerous paper targets.
There were nine knives, three swords of varying lengths and a BB gun.
In addition, police discovered personal notes, memoirs and thoughts collected by Adam, including seven journals and drawings by him. There were also newspaper clippings, drawings and medical bills police have been scrutinizing to develop a psychological profile of the gunman.
Among the newspaper clippings recovered was a New York Times article from February 2008 about a school shooting at Northern Illinois University.
A recovered holiday card from Nancy to Adam contained a Bank of America check made out to him for the purchase of a C183 firearm.
The guns use in the shooting were apparently all purchased by Nancy. The gun locker at the Lanza home was open when police arrived, according to authorities. It was unlocked and there was no indication that it had been broken into.
"After consultation with the investigators, it was decided that much of the information in the search warrants would not sought to be sealed and that the release of the above basic crime scene information would not jeopardize the active and continuing criminal investigation into this unprecedented tragedy," Stephen Sedensky III, state's attorney for the Judicial District of Danbury, said in a statement Thursday.
"This is an active, ongoing investigation," Sedensky wrote. "No conclusions have been reached and no final determinations have been made."
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