NOTE: This post will be continually updated as new information comes in. Video and photos are below. All times Eastern.

UPDATE 6:30 p.m.: Originally it was thought that Adam Lanza, the gunman, shot his mother at the Sandy Hook Elementary school, where she was a teacher's aide. ABC has learned that, in fact, Nancy Lanza was killed at her home (by her son) prior to the massacre. He then drove to the school, where he killed 20 children and six adults, before killing himself.

UPDATE 5:25: While most of the victims' names have not been revealed (authorities are still in the identification stage for some, and in the process of informing the families of the others), one name we do know is Dawn Hochsprung, the principal of Sandy Hook Elementary. Below is a photo from CBS:


UPDATE 3:45: Lieutenant Vance (pictured) answered some reporters' questions and provided some additional information and clarity on previous news. He said that among the dead are 20 children, two of whom were taken from the school to a hospital, where they were pronounced dead, and six adults. This does not include the shooter, who also died at the scene. Lt. Vance said the shootings all occurred "in one section of the school, in two rooms."

There is a "secondary crime scene" in Newtown, where one adult is dead. Lt. Vance did not elaborate on that.

The shooter's name has been released. It is Adam Lanza, age 20. Previously, it had been reported that the gunman was Mr. Lanza's older brother, Ryan. Ryan Lanza is being questioned by the FBI in Newark, N.J.

Connecticut State Police spokesman Lt. J. Paul Vance briefs the media (Photo by Jared Wickerham/Getty Images)

UPDATE 3:30: President Obama gave some brief remarks on today's events. Here is a partial transcript:

This evening, Michelle and I will do what every parent in America will tonight, which is hug our children a little tighter and tell them that we love them, and we’ll remind ourselves how deeply we need them. ... Our hearts are broken today for the parents, grandparents, sisters and brothers of these little children, and for the families of the adults that were lost. ... Our hearts are broken for the parents of the survivors as well. For as blessed as they are to have their children come home tonight, they know that their children’s innocence has been torn away from them too early.

UPDATE 2:20: CBS is reporting that one of the victims is the shooter's mother, who was a teacher at the school.

UPDATE 1:55: The Associated Press is reporting that the shooter used a .223 caliber rifle, not handguns, though this has not been confirmed.

UPDATE 1:45: "The scene is secure. The public is not in danger," said Lieutenant Paul Vance at a press conference. Connecticut Governor Dan Malloy has spoken with President Obama, and he is in continual talks with agencies at the site of the incident.

UPDATE 1:15: Sources say that the shooter was a 20-year-old man from either New Jersey or Connecticut. It's uncertain as of yet whether he took his own life or was killed by law enforcement.

UPDATE 12:50: Multiple reports are coming in now with much larger numbers of fatalities. CNN is reporting "close to 20" killed, with at least 10 of those children. CBS says 27 are dead, 14 of which are children. NBC says eight adults and 18 children were killed.

UPDATE 12:17: According to an eyewitness inside the school, three of the shooter's targets appear to have been the principal, the vice principal and the school psychologist, who went out into the hallway when the first shots were fired. The vice principal was wounded in the foot or leg and came crawling back, and the principal and psychologist did not return and may be among the dead. There "must have been 100 rounds fired," according to the witness.

UPDATE 11:50 a.m.: CNN has confirmed that one of the victims is a student at the school. Danbury, Connecticut, mayor Mark Boughton has said that "at least three people were wounded and are in 'very serious' condition" at that town's hospital.

The Hartford Courant has confirmed that one person at Sandy Hook Elementary School in Newtown, Connecticut, was killed Friday morning in a shooting. Other victims have been reported as well. The shooter has been killed.

Multiple shots were heard during morning announcements at around 9:40 a.m., after which police were called. Students have been evacuated, and police and state troopers are on the scene.

Douglas Healey/Getty Images
Douglas Healey/Getty Images
Douglas Healey/Getty Images
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