20 Children, 7 Adults, Killed in Shooting at Elementary School in Connecticut, USA

Visit NBCNews.com for breaking news, world news, and news about the economy

A gunman shot and killed at least 20 young schoolchildren and 6 adults, including the school's principal, today at Sandy Hook Elementary School, a Kindergarten-4th Grade school in Newtown, Connecticut, USA, before killing himself in one of the classrooms.

The gunman has been identified as the 20-year-old son of one of the teachers at the school, and a federal law enforcement source said the man had headed directly for his mother's classroom, indicating his mother may have been his primary target - but noted that "the shooter came armed with clear intention of mass killing." 

There were reports that another body, possibly a family member, had been found at an off-campus location connected with the shooter. Details were still emerging about the shooting, the gunman, and the circumstances of the incident by Friday evening on the East Coast.

Update [Sunday 12/16/12]:

Reports on the Friday of the shooting initially indicated that the gunman was the 24-year-old son of one of the female teachers at the school, and a federal law enforcement source said the shooter had headed directly for his mother's classroom, indicating his mother may have been his primary target, but that "the shooter came armed with clear intention of mass killing."  

However, it was later established that the gunman had shot his mother at their home before driving to the school and going on his rampage, and was in fact 20 years old, and had been misidentified as his older brother.