THE United States is today coming to terms with its worst-ever school massacre after 26 people, including 20 young children, were killed by a gunman who opened fire at a Connecticut elementary school.
The gunman, armed with semi-automatic pistols targeted two classrooms before he was later found dead at the scene.
In all, 28 people, including the gunman and the killer's mother, found at a different site, were killed.
Frightened pupils were rushed out of Sandy Hook Elementary in Newtown, 100 km north-east of New York City, as police and other law enforcement officials responded to an early morning emergency call.
Eighteen children were pronounced dead at the school, while two died after being moved to a local hospital.
Seven adults, including the gunman, were killed and one person was injured at the school, while one person was killed at another site in Newtown, according to Lt Paul Vance of the Connecticut State Police.
Hours later, flags flying from the US Capitol building and the White House were lowered to half mast.
A visibly distressed Barack Obama, pausing repeatedly to compose himself as he addressed the nation and at one point raising a finger to wipe a tear from the corner of his left eye, spoke of the tragic waste of young lives, with most of those dead "beautiful little kids between the ages of five and 10 years old."
"We've endured too many of these tragedies in the past few years. And each time I learn the news, I react not as a president, but as anybody else would as a parent. And that was especially true today."
Referring to the young victims, he added: "They had their entire lives ahead of them - birthdays, graduations, weddings, kids of their own... So our hearts are broken today for the parents and grandparents, sisters and brothers of these little children, and for the families of the adults who were lost."
The Associated Press, quoting an unnamed law enforcement official, named the perpetrator as Adam Lanza, although this was not confirmed at a mid-afternoon briefing attended by the Connecticut Governor, Dan Malloy.
Adam Lanza's older brother, Ryan, said to be from Hoboken, New Jersey, was being questioned after earlier being mistakenly identified as the killer by law enforcement officials, according to AP.
The news agency later reported an unnamed official saying Ryan Lanza had no involvement in the shooting.
Mr Malloy later told a press briefing: "Evil visited this community today." The day for the victims ended "in a way none of could have imagined and frankly even as we stand here today we still can't imagine", he added.
The Lanza brothers' mother was reported to be a kindergarten teacher at Sandy Hook Elementary.
According to the official briefing, the shooting took place in one section of the school.
The local Hartford Courant newspaper reported that Lanza had attended Sandy Hook, though again this was not verified by the authorities.
The killer is said to have shot the principal before proceeding to his mother's kindergarten class.
Although his mother was reported to be dead, it was unclear whether her body had been found at the school or at the other Newtown site under investigation last night.
Authorities were also initially silent about how the killer, who was reported to be carrying at least two and possibly as many four weapons, died.
NBC News reported that the weapons used in the shooting were bought legally, and registered to the suspect's mother.
Some 700 pupils regularly attend the kindergarten-to-fourth-grade school, located near a quiet stretch of suburban woodland in Newtown.
If residents here last night were bewildered to find themselves in the shadow of unfathomable evil then the picture presented by their bucolic town goes some way to explain why.
Unusually wide, Main Street tracks generously between mostly proud homes, some guarded by Connecticut dry-stone walls, all with wreaths on their doors for the season.
This is the New England that Norman Rockwell captured in his drawings - a place supposedly insulated from the hurly-burly of the world beyond.
No longer. The wreaths will be minus their cheery red ribbons and mistletoe flourishes as they become symbols instead of mourning, silent tributes to the 20 children who are now gone and the six adults whose only concern when they arrived for work yesterday morning was to care for them as they did every day.
With the death toll rising through the day, shocked pupils described the scene as the killer arrived on what was a sunny Friday morning (US time).
"I was in the gym and I heard like seven loud booms, and the gym teachers told us to go in the corner, so we all huddled," one student told NBC Connecticut during its live broadcast.
"And I kept hearing these booming noises. And we all … started crying." She added: "All the gym teachers told us to go into the office where no one could find us.
So then a police officer came in and told us to run outside. So we did and we came in the firehouse and waited for our parents."
The shooting is the latest such incident to hit America, with the number dead reported to be more than double those killed at Columbine High School in Colorado, where 13 people were killed in 1999.
More recently, shootings have occurred in Colorado, which was hit by an attack at a midnight showing of the new Batman film, and a Sikh temple in Wisconsin.
At Virginia Tech, a university, 32 people were left dead following a massacre by a student in 2007. On each occasion, there have ritual rumblings about the need for greater gun control, but little meaningful action.
Referring to the litany of tragedies, the President yesterday called for another effort in that direction. "As a country, we have been through this too many times... We're going to have to come together and take meaningful action to prevent more tragedies like this, regardless of the politics," he said.
At dusk many of the parents of the dead children were receiving care and grief counselling at the Newtown fire station. At least two churches in the town were planning vigils for the victims of the shooting.
Lt Vance meanwhile appealed to journalists to keep a respectful distance. "It is very, very difficult scene" in there, he said bluntly. "It is a very tragic scene".
Queen sends message of support
The Queen sent a message, signed "Elizabeth R" to President Obama expressing her sorrow at the shootings and sending her condolences to the US.
"I have been deeply shocked and saddened to learn of the dreadful loss of life today in Newtown; particularly the news so many of the dead are children," she told him. "Prince Philip joins me in extending our heartfelt sympathy to you and the American people at this difficult time. The thoughts and prayers of everyone in the United Kingdom are with the families and friends of those killed."
David Cameron said on Twitter that the deaths of so many children were "truly heartbreaking".
Eyewitnesses in their words
Brendan Murray, a student, told the WABC station he was in the gym when he heard screams: "I heard screaming and I thought a custodian was knocking down things. Police came in, teachers yelled to get to a safe place. Police were knocking on the doors, leading us down, quick, quick." He escaped with classmates and added: "We were all really happy that we were alive."
Brenda Lebinski rushed to the school where her daughter is in the third grade. "It was horrendous," she said. "Everyone was in hysterics - parents, students. There were kids coming out of the school bloodied."
Stephen Delgiadice said his eight-year-old daughter, who was unhurt, heard two big bangs, and teachers told her to get in a corner. "It's alarming, especially in Newtown, Connecticut, which we always thought was the safest place in America," he said.
Richard Wilford said his seven-year-old son, Richie, heard a noise that "sounded like what he described as cans falling". A teacher went out to check on the noise, came back in, locked the door and had the kids huddle up in the corner until police arrived. "There's no words," said the boy's father. "It's sheer terror, a sense of imminent danger, to get to your child and be there to protect him."