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Newtown Report: Lanza killed 26 in 11 minutes at Sandy Hook

Adam Lanza shot and killed 26 people, including 20 first-graders, in less than 11 minutes, according to a newly released report on the Dec. 14, 2012 massacre at Sandy Hook Elementary School in Newtown, Conn.

Pictures: Conn. elementary school shooting

In Lanza’s home, police found a spreadsheet of mass murders, photographs of Lanza holding a gun to his head, multiple firearms, and “many edged weapons, knives, swords, spears, etc.”

The report, which was prepared by Connecticut State Attorney Stephen J. Sedensky III, found that Lanza, 20, had a “preoccupation with mass shootings, in particular the Columbine shootings.”

Sometime between 8 a.m. and 9 a.m. on the morning of the massacre, police believe Lanza used a .22 caliber Savage Mark II rifle to shoot and kill his mother in her bed. He then drove his 2010 Honda Civic to the school, parked in a “No Parking” zone, and at approximately 9:30 a.m., shot through the plate glass windows of the locked doors leading into the school. He used a Bushmaster Model XM15-E2S rifle to kill his victims, then shot himself in the head with a Glock 20, 10mm handgun.

The first 911 call from the school was received at 9:35 a.m., and police arrived four minutes later. One minute after that, Lanza shot himself.

At the home where Lanza lived with his mother, police found Adam Lanza’s bedroom windows taped over with black trash bags. Police also found multiple articles about school shootings, including one about the 2008 shooting at Northern Illinois University and another “pertaining to the shooting of school children” in 1891.

“Investigators found a large number of firearms and related items in the home,” the report states. “All firearms involved in these incidents were legally purchased by the shooter’s mother over the years.”

Despite the long investigation, a clear motive remains elusive: "The obvious question that remains is: 'Why did the shooter murder twenty-seven people, including twenty children?' Unfortunately, that question may never be answered conclusively...The evidence clearly shows that the shooter planned his actions, including the taking of his own life, but there is no clear indication why he did so, or why he targeted Sandy Hook Elementary School."

The report also states that at the time of the shooting, Adam Lanza had not been in touch with his older brother, Ryan, since 2010. Lanza's relationship with his father also apparently "deteriorated" in 2010. Lanza's mother, Nancy, was not allowed in his room.

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