Connecticut School Shooting: What set Adam Lanza off? (VIDEO)

Distraught leave the fire station after hearing news of their loved ones from officials December 14, 2012 in Newtown, Connecticut. A young gunman slaughtered 20 small children and six teachers on Friday after walking into a school in an idyllic Connecticut town wielding at least two sophisticated firearms. The toll was the second deadliest of the recurrent school shootings in the United States. Connecticut State Police spokesman Lieutenant Paul Vance said 18 children were shot dead inside Sandy Hook Elementary School and that two more died of their wounds in hospital. Six adults at the school were killed, Vance said, before the killer was shot -- either by his own hand or police. US media said the school principal was among those killed. AFP PHOTO / DON EMMERT (Photo credit should read DON EMMERT/AFP/Getty Images)

(CBS) NEWTOWN, Conn. - Many questions remain about the identity and the psychological state of Adam Lanza, the young man who went on a shooting spree Friday morning at Sandy Hook elementary school. Senior CBS Correspondent and former assistant director of the FBI John Miller offers some possible answers.

Pictures: Conn. elementary school shooting

Miller reports friends of Adam Lanza told CBS News that he was "socially awkward and in some cases, he made people uncomfortable who didn't know him well."

Miller also notes that the alleged shooter does not appear to have a Facebook or online identity and seemingly kept to himself.

Miller speculated that "the problems between [Adam] and his mother resulted in her murder and then he set off to kill the other thing in her life that she loved."

Complete coverage of the Sandy Hook Elementary School massacre