`` It 's the unthinkable , really . '' NEW : An ex-school official says Lanza sometimes withdrew `` into his own little world '' Authorities look at smashed computer parts from the gunman 's home , an official says . Lanza visited at least one gun range with his mother , an ATF spokeswoman says . Comment:
NEW : An ex-school official says Lanza sometimes withdrew `` into his own little world '' Authorities look at smashed computer parts from the gunman 's home , an official says . Lanza visited at least one gun range with his mother , an ATF spokeswoman says . Comment: