NBC aired this report that a rifle was NOT used in the shooting, and that Lanza had an altercation at the school days before the incident, and that he also tried to purchase a rifle, but was denied. I have tried to find this report on the web, it proves difficult to do so, as it does not support the anti-guns assertion that an assault weapon was used in Sandy HooK.
http://www.youtube.com/watch?v=30sjtuXcvOE