In less than five minutes, a gunman shot his way into Sandy Hook Elementary School and killed 26 people inside, then took his own life, leaving more than 150 spent rounds in his wake, according to documents released Thursday.

Danbury State's Attorney Stephen Sedensky says Adam Lanza killed 20 first-graders and six adults using a Bushmaster .223-caliber rifle before taking his own life with a Glock 10-mm. handgun. Sedensky says Lanza had another loaded handgun with him inside the school, as well as three, 30-round magazines for the Bushmaster.

The documents say Lanza was found dead in the school wearing a bulletproof vest and military-style clothing, according to the Associated Press.

A loaded 12-gauge shotgun was found in the glove compartment of the Honda Civic Lanza drove to the school with two magazines containing 70 rounds of Winchester 12-gauge shotgun rounds.

An arsenal of weapons, including guns, more than 1,000 rounds of ammunition, Samurai swords, knives and a bayonet were found in Lanza's Connecticut home following the Dec. 14, 2012, massacre, according to search warrants.

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Investigators also found a gun safe belonging to the shooter's mother, Nancy Lanza. There was no evidence the safe had been broken into, according to CTnow.com. Lanza shot and killed his mother prior to the shooting rampage at the school, police said.

The extensive inventory of the evidence seized from Lanza's home and the car he drove to carry out the massacre provided glimpses into the world of the reclusive gunman. Prosecutors until now had made few details available, despite pressure to do so from the governor, who criticized leaks to the press and lawmakers who clamored for more details as they craft legislation on mental health and gun control.

At the house, investigators found books about autism and Asperger's syndrome as well as an NRA guide to pistol shooting.

Police said they found a smashed computer hard drive, a gaming console and a gun safe in Lanza's bedroom. An unnamed source told investigators that Lanza was an avid gamer who played "Call of Duty" and other games and rarely left his home.

Investigators found articles on other shootings and a holiday card containing a check made out to Adam Lanza for the purchase of a firearm, authored by his mother, Nancy Lanza.

Police also found three photographs of an unidentified dead person covered in plastic and blood, according to CTnow.com.

Documents indicate authorities found a brown gun safe with shotgun shells and numerous boxes of bullets. In a bedroom closet, they found ear plugs, a handwritten note regarding ammunition and magazines, paperwork on guns and a metal bayonet.

In a top drawer of a filing cabinet, they found paper targets. In a duffel bag, they found ear and eye protection, binoculars, numerous paper targets and Lanza's NRA certificate.

The search warrants released Thursday made no mention of a massive spreadsheet Lanza reportedly compiled containing extensive research on previous mass murders.

A Danbury Superior Court judge on Wednesday granted a request by Sedensky, the prosecutor overseeing the investigation, to withhold some details. Sedensky asked to redact the name of a witness, saying the person's safety might be jeopardized if the name were disclosed. He also asked that the release not include other information such as telephone numbers, serial numbers on items found and a few paragraphs of an affidavit.

Authorities have said it will take until June or later for the investigation to be completed.

Senate President Donald E. Williams Jr. said this week that legislative leaders hope to review the search warrant documents before finishing work on a bipartisan bill that addresses gun control and other issues related to the massacre.

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The Associated Press contributed to this report.