President Obama: ‘Shame on us if we’ve forgotten’ Newtown. (The Washington Post)

Adam Lanza lived in a gun lover’s house. He was a gamer, a loner, an enigma. He relied on his mother for everything until the moment he shot her in the forehead.

That hazy, disordered portrait, which emerged after Lanza killed 26 people at Sandy Hook Elementary School in December, was filled out Thursday when the contents of his interior life were divulged in unsealed search warrants that revealed a home brimming with weaponry, electronics and grim photos.

But the revelations spurred only more mystery.

Investigators found journals but didn’t say what was written inside. They found rifles and a trove of ammunition but didn’t (or couldn’t) explain why the arsenal was apparently unsecured. They found books on Asperger syndrome and autism, as well as a book titled “Train Your Brain to Get Happy.” They found a busted hard drive, but what was on it? They found samurai swords, knives, a bayonet, video-game consoles, pictures of a bloody dead body and a news clipping about another school killing.

They found clues — lots of clues — but if there is context to the clues in the form of motive, authorities either don’t know or aren’t saying. Three months after Lanza shattered a small town, setting off a renewed gun control debate, there still is no answer to the question of why he targeted so many schoolchildren in Newtown, Conn.

Police recovered 165 items from Adam and Nancy Lanza's home.

“This is an active, ongoing investigation,” Danbury State’s Attorney Stephen J. Sedensky III said in a statement. “No conclusions have been reached, and no final determinations have been made.”

The new details about Lanza came a day after authorities in Arizona released a trove of records about Jared Lee Loughner, the disturbed young man who tried to kill then-Rep. Gabrielle Giffords (D-Ariz.) in 2011. In that case, Loughner’s parents had recognized red flags but did not act on recommendations to have their son mentally evaluated.

If Lanza’s mother, Nancy, had recognized that her son was an imminent threat, the search warrants released Thursday don’t offer any evidence of that. Printed e-mails were found in the living room of their two-story colonial home, but the contents — again — are unknown. Nancy had gone on a getaway to New Hampshire in the days before her son’s attacks, according to previous reports.

Although the clues in the Lanza case aren’t yet adding up to the why, investigators have nailed down the how. In his statement, Sedensky painted a chilling picture of the attack, saying the shooting, in which Lanza fired at least 154 rounds, lasted less than five minutes. The carnage ended only when Lanza killed himself with a Glock 10mm handgun

He shot all of the victims with a Bushmaster .223-caliber XM-15 rifle loaded with a 30-round-capacity magazine. Lanza had other handguns and three still fully loaded 30-round magazines on him, Sedensky said. Empty and near-empty magazines were found nearby.

Police found a 12-gauge shotgun in the passenger area of his car, which was parked outside the school. Authorities said that the guns used in the attack “were apparently all purchased by the shooter’s mother” and that a gun locker at his home was “unlocked and there was no indication that it had been broken into.”

Lanza and his mother often went to shooting ranges together. He killed her in bed with a .22-caliber rifle before heading to the school, authorities said.

Federal, state and local authorities have been tight-lipped about their investigation. Several media organizations, including The Washington Post, had filed motions seeking the five search warrants disclosed Thursday, and they were released only after a 90-day seal requested by prosecutors ended this week.

Connecticut Gov. Dan Malloy (D) had asked authorities to release details in the case amid an intense gun control debate in the state. Family members of the victims were reportedly briefed on the search warrants Wednesday night. Sedensky requested, and was granted, several redactions in the documents, including the name of a witness and phone and credit card numbers.

Two dramatic pieces of evidence leaked by unnamed sources to other news outlets were not reflected in the search warrant releases. The Hartford Courant has reported that Lanza researched Anders Behring Breivik, who killed 77 people in Norway two years ago. Also, this month the New York Daily News said that a senior state police official told a law enforcement conference that Lanza had constructed a seven-foot-long spread­sheet on previous mass murders.

Friends of Nancy Lanza have said Asperger syndrome had been diagnosed in Adam. Asperger is on the autism spectrum and isn’t associated with violence. In his home, police found a book titled “Look Me in the Eye: My Life With Asperger’s,” computers and video-game consoles, Lanza’s report card from Sandy Hook and a holiday card his mother gave him containing a check for the purchase of a firearm. More than 1,700 rounds of ammunition were discovered in shoe boxes, closet shelves, cabinets and an unlocked safe. There were two rifles, a BB gun and a starter pistol. Adam’s room had a gun safe.

According to the unsealed documents, a witness told authorities that Lanza was a “shut in” and “avid gamer” who played “Call of Duty” — descriptions largely in line with what acquaintances of the family told the media after shooting. The witness also said the school where the killings took place was his “life.” That description doesn’t mesh with published reports indicating that Lanza, although brilliant, bounced in and out of Newtown schools.

There was no evidence confirming or denying reports that Lanza had a sensory integration disorder, and there was no reference to the briefcase that he often carried to school. There were documents related to Lanza’s PSAT tests. Lanza had taken classes at a nearby college, and his mother was said to be looking at colleges for him.

The search warrants indicated that authorities found certificates from the National Rifle Association in Adam and Nancy’s names. A book titled “NRA Guide to the Basics of Pistol Shooting” was also found.

The NRA sharply disputed any connection between the Lanzas and the gun rights organization. It said in a statement, “There is no record of a member relationship between Newtown killer Adam Lanza, nor between Nancy Lanza, A. Lanza or N. Lanza with the National Rifle Association.”