Twenty-seven people, including 20 children, are dead after a shooting at Sandy Hook Elementary School.

Another person was found dead at 36 Yogananda St. in Newtown, sources told The Courant. 

The shootings at the school took place in two rooms, one of which is a kindergarten classroom, sources said. One entire classroom is unaccounted for.

The shooter is dead inside the school, and the situation is secure, said State Police Lt. J. Paul Vance.

There were conflicting reporters about the identity of the shooter, but the Associated Press, citing a law enforcement official, identified him as Ryan Lanza and said his younger brother is being held for questioning as a possible second shooter. Local authorities would not confirm the name of the shooter.

CNN also initially identified the shooter as Lanza, but it no longer is.

The law enforcement official said the boys' mother, Nancy Lanza, works at the school as a teacher. She is among the dead, an official said.

The official also said Ryan Lanza's girlfriend and another friend are missing in New Jersey.

Another official, speaking on condition of anonymity because the investigation was still under way, said the gunman apparently had two guns. A law enforcement official in Washington said one of the guns was a .223-caliber rifle.  

President Obama, in an emotional address to the nation Friday afternoon, said "These neighborhoods are our neighborhoods, and these children are our children."

“I know there’s not a parent in American who doesn’t feel the same overwhelming grief that I do," he said. "The majority of those who died today were children, beautiful little kids between the ages of 5 and 10 years old. … They had their entire lives ahead of them. Birthdays, graduations, weddings, kids of their own." 

“Among the fallen were also teachers, men and women who devoted their lives to help their children achieve their dreams,” he said. 

Like other parents around the country, Obama said, “This evening, Michelle and I will ... hug our children a little tighter and tell them that we love them … but there are families in Connecticut who cannot do that tonight.”

“While nothing can fill the space of a lost child or a loved one, all of us can extend a hand to those in need, to remind them that we are there for them, that we are praying for them, that the love they felt for the ones they have lost will endure in their memories but also in ours.”

Public records show that Ryan Lanza lived at 36 Yogananda St. at one point, and he is also listed as living at 1313 Grand St. in Hoboken, N.J. Police are searching that residence as well, sources say.

Lanza was a "pretty quiet" student at Newtown High School said Chris Fulcher, 18, who lives in the Yogananda Street neighborhood and used to ride the bus with Lanza.

Three people were brought to Danbury Hospital, but their condition is unknown. The emergency room is on lockdown. 

Shortly after 9:40 a.m., police reported that a shooter was in the main office of the school. A person in one room had “numerous gunshot wounds,” police said.

Groups of students — some crying, some holding hands — were being escorted away from the school by their teachers. Some students were still in the school at 10:30 a.m., parents said.

Police were still searching the school at 11 a.m., and police dogs were brought in. Around noon, the triage area was broken down, stretchers were taken away and the SWAT team left the building.