Authorities in Connecticut on Friday released a final report on the December 2012 elementary-school massacre in Newtown, Conn., which revealed the shooter's mother had ties to the National Rifle Assocation (NRA).

The report contains hundreds of photos, including items authorities seized from the home of shooter Adam Lanza and his mother, Nancy, both of whom are deceased.

Some of the photos showed Nancy Lanza's NRA basic pistol training course certificate, as well as various knives, firearms, and several articles on school shootings with which Adam Lanza was reportedly obsessed.

Back in March, separate police reports revealed that authorities discovered NRA certificates among the Lanzas' possessions. In a sharply worded statement then, the NRA said that neither were members.

"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. Reporting to the contrary is reckless, false and defamatory," the statement said. According to the NRA's website, the association does not give out formal certificates for membership.

Nancy Lanza was described by friends and acquaintances after the shooting as a gun enthusiast. She often took her two sons to gun ranges around Newtown.