Law enforcement officials tell CBS that Adam Lanza, who killed 26 children and teachers in Newtown, Connecticut, was trying to outdo Anders Breivik, who killed 77 in Norway in 2011. Breivik bombed downtown Oslo before shooting teenagers gathered at a nearby island for summer camp. Officials say Lanza targeted Sandy Hook because it was the "easiest target" with the "largest cluster of people." Sources also say evidence shows Lanza was acting out fantasies taken from videogames. A police spokesman commented Monday that it is still "mere speculation" to try to understand Lanza's motives.