Police aren't say what may have motivated a man to open fire inside two classrooms at a Connecticut elementary school today, but a law enforcement official who has been briefed on the investigation says the gunman was believed to suffer from a personality disorder.

Twenty-six people, including 20 children, were killed in the shooting rampage before the gunman shot and killed himself.  Police say another adult was found dead at a second location.

A law enforcement official has identified the gunman as 20-year-old Adam Lanza, the son of a teacher at the Sandy Hook Elementary school. The official says Lanza killed his mother at their home before driving his mother's car to the school.

According to ABC News:

Late today, police said Nancy Lanza's body was found in the family home. According to sources, Lanza shot his mother in the face, then left the house armed with at least two semi-automatic handguns and a semi-automatic rifle.

Police say the killer carried two handguns into the school, while a rifle was found in the back of a car. They say the shootings took place in two classrooms, but they are not providing details on exactly how it unfolded.

Students and their parents describe teachers locking doors and ordering the children to huddle in classroom corners or hide in closets as shots echoed through the building. Authorities said the shootings took place in two nearby classrooms, but they gave no details on exactly how they unfolded.

Connecticut State Police Lt. J. Paul Vance 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.

Police Provide Total Dead in School Shooting

Lt. Vance said the shootings all occurred “in one section of the school, in two rooms.”

Adam Lanza 's older brother, Ryan Lanza, 24, has been "extremely cooperative" and is not under arrest, according to law enforcement.

The official tells The Associated Press that Ryan, of Hoboken, N.J., is still be being questioned but is not in custody and is not believed to have any connection to the school killings.

The official spoke on condition of anonymity because he was not authorized to speak publicly on the investigation.

The official says Ryan Lanza's computers and phone records were being searched but only "in an abundance of caution." He says Ryan told authorities he had not been in touch with his brother in recent years.

Shooter May Have Targeted Specific Classroom

Speaking on condition of anonymity, the official said Adam Lanza died from a self-inflicted gunshot wound.

Sandy Hook Elementary School in Newtown is about 60 miles northeast of New York City. State police say Newtown police called them around 9:40 a.m. A SWAT team was among the throngs of police to respond.

Exclusive: Local Resident with Family in Newtown Talks About Shooting

The official said three weapons were used in the attacks, including a .223 Bushmaster, a Glock, and a Sig-Sauer. No word on the models of those weapons.

According to CNN:

A law enforcement official familiar with the investigation says the three guns found at the shooting site were legally purchased by Nancy Lanza, the mother of the suspect in the shooting. According to the law enforcement official, the Glock and Sig Sauer handguns were found inside the school with the deceased gunman. The Bushmaster was found in a car outside the school. The official did not know if the car was registered to the gunman, to his mother or to someone else.


.223 Bushmaster/Bushmaster Firearms

ABC Radio Report: Sandy Hook School Shooting

ABC News Report

According to a witness who spoke with CNN, the principal and the school's psychologist were among those killed.

The principal and a school psychologist were killed, according to a parent who was at the school during the incident. The vice principal was shot in the foot or the leg, said the eyewitness, who has a second-grader at the school, and who talked to our colleague Meredith Artley. "The principal, vice principal and the school psychologist went into the hall. Only one person came back. It was the vice principal. The vice principal was shot in the leg or foot and came crawling back from the hall."

According to Artley students being evacuated from the school had to walk by the bodies of some of the victims.

Schoolchildren and their parents are describing the scene at a Connecticut elementary school today, as teachers locked doors and ordered the children to huddle in the corner or hide in closets.

Shots rang through the building, as a gunman killed 26 people, including 20 children.

One man says his 6-year-old son was in class when the gunman burst in and shot the teacher. He says his son "grabbed a bunch of his friends and ran out the door."

The father of one 7-year-old says the boy heard a noise that sounded like "cans falling." A teacher went out to check on the noise, came back in, locked the door, and had the kids huddle in the corner until police arrived.

A teenager who rushed to the school to check on his sister, after hearing the gunfire from his nearby home, says the 9-year-old girl had heard a scream come over the intercom at one point.

As they left the school, the children -- some crying, others looking frightened -- were told by police to close their eyes, so they wouldn't see the carnage around them.

'Go With Your Gut Feeling'

A tearful President Barack Obama says the country's leaders must "take meaningful action" regardless of politics in response to the mass shooting at a Connecticut elementary school. He did not say what that action should be.

The president teared up, at times using an index finger to wipe at the corner of his eyes, as he addressed the nation from the White House. He also paused repeatedly as he struggled to keep his composure while speaking of the children - ages 5 to 10 - who had died and the life milestones they now would miss.

He said, "Our hearts are broken today." Obama said the victims were "beautiful, little kids" who "had their entire lives ahead of them" -- and he recited future milestones lost: "birthdays, graduations, weddings, kids of their own."

President Obama Speaks About School Shooting

Shortly before speaking, Obama ordered that U.S. flags be flown at half-staff on public grounds through Tuesday.

As he spoke, two senior aides standing nearby cried and held hands.

Obama, who began his comments with no greeting, ended them with words of Scripture, and walked away in silence.

A White House spokesman says this isn't the day for a discussion about gun control. Jay Carney was responding to reporters' questions on that issue, and President Barack Obama's campaign promises on gun control, in the aftermath of today's deadly shooting at a Connecticut elementary school.

During his time in office, mass shootings have shaken communities in Wisconsin, Texas and Colorado.

Although the White House isn't getting into the issue of gun control today, others are. Democratic congressman Jerrold Nadler of New York said in a statement, "If now is not the time to have a serious discussion about gun control and the epidemic of gun violence plaguing our society, I don't know when is."

Relatives of those killed in this summer's Colorado theater shooting are reacting with outrage to Friday's mass shooting at a Connecticut elementary school - and demanding that the nation finally address gun control.

Tom Teves lost his son, Alex, in the July 20 theater shooting in the Denver suburb of Aurora. Teves insisted that there is no need for the public to have access to weapons like the one allegedly used by the gunman in Newtown, Conn.

The latest mass shooting came a day after Colorado's governor called on lawmakers to start debating gun control measures.

University of Colorado student James Holmes is accused of purchasing a semi-automatic rifle and other weapons before killing 12 people and wounding 70 others in July.

House Speaker John Boehner has ordered flags at the U.S. Capitol lowered because of the shootings at a Connecticut elementary school that claimed 26 victims, including 18 children.

In a tweet, the Ohio Republican said he issued the order "in tribute to families and victims" at the Sandy Hook Elementary School in Newtown, Conn.

Connecticut Governor Malloy Speaks About Shooting

The killings appeared to be the second deadliest school massacre in the country's history, with only the 2007 killings at Virginia Tech claiming more victims - 32 plus the gunman.

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The shooting was reported at Sandy Hook Elementary School in Newtown, in western Connecticut. State police say Newtown police called them at about 9:40 a.m. about the reports.

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