NEWTOWN, Conn. -- CBS News has identified the gunman in one of the deadliest school shootings in history as Adam Lanza. His older brother, Ryan, is being questioned by police, according to CBS News.
Police say they found the gunman's body inside the school, which is now secure. Authorities recovered two semi-automatic weapons at the scene.
CBS News also says the gunman's mother worked as a teacher at the school. Some of the victims were her students.
Police say the gunman killed 20 children, and six adults before taking his own life.
The shooting began just after 9 a.m. CBS News reports an argument erupted at the front office, followed by gunfire.
The CBS affiliate in Hartford, WFSB-TV, reports someone tripped the school loudspeaker so that everyone in the school could hear the commotion, which may have helped save lives.
Police also found the body of an adult at a second crime scene. Investigators would not say whether the victim is related to the gunman.