Police release Sandy Hook shooting documents

New video released by Connecticut State Police shows the inside of Sandy Hook gunman Adam Lanza's house following the shooting.

The police footage shows numerous rounds of ammunition, gun magazines gun cases, and a scratched hard drive

A report released on the gunman of the Sandy Hook massacre reveals that Adam Lanza "was undoubtedly afflicted with mental health problems; yet despite a fascination with mass shootings and firearms, he displayed no aggressive or threatening tendencies".

Lanza became obsessed with the 1999 bloodbath at Columbine High in Colorado and other mass killings, the report said. He also kept a spreadsheet ranking mass murders.

The report also said that in 2005, he was diagnosed with Asperger's disorder - an autism-like condition that is not associated with violence - and that he lacked empathy for others and behaved strangely.

Connecticut state police released a trove of documents over the Sandy Hook massacre including footage of the school facade, including close-up images of bullet-shattered windows, and a video tour through the cheerfully decorated home the shooter, Adam Lanza, shared with his mother, Nancy Lanza.

Connecticut state police released thousands of pages of documents on Friday tied to their investigation of the shooting massacre at Sandy Hook Elementary School last year that killed 20 children and six adults.

Commissioner Reuben Bradford said in a letter introducing the documents:

Police in Connecticut have released pictures showing the bloody aftermath of the aftermath of the Sandy Hook Elementary school shooting.

Read: Police release Sandy Hook massacre documents

The shooting was one of the deadliest incidents of gun violence in US history. The gunman Adam Lanza who also shot and killed his mother before the rampage, killed 20 children and six adults at the school before turning the gun on himself when police showed up.

Read: Devastated Sandy Hook parents urge greater gun control

The release comes about a month after the state Division of Criminal Justice released a report on Newtown that concluding that 20-year-old Lanza acted alone, and that his motive may never be known.

Read: Little has changed since the Sandy Hook massacre

The acting superintendent of Newton public schools sent an email to parents yesterday to inform them of the planned release by police of the thousands of documents relating to the investigation into the Sandy Hook Elementary shooting. John Reed said:

Police in Connecticut have released thousands of pages of documents from their investigation into the Sandy Hook Elementary School massacre that killed 20 children and six adults.

The documents include videos, pictures, text and 911 emergency calls received by state police on the day of the shooting, December 12, 2012.

Read: One year anniversary of Sandy Hook massacre