The peace and security of the suburban Connecticut community of Newtown has been shattered after a gunman attacked a primary school in one of the worst mass shootings in US history.
The gunman - who according to a media report carried four weapons and wore a bulletproof vest - was dead inside Sandy Hook Elementary School, state police Lieutenant Paul Vance told a news conference.
Vance said authorities found 18 children and seven adults, including the gunman, dead at the school, and two children were pronounced dead later after being take to a hospital.
Another adult was found dead at a related crime scene in Newtown, he said, bringing the toll to 28. CNN reported the dead person was the shooter's mother.
He has been named as Adam Lanza, the son of a teacher at the school.
His older brother, Ryan, 24, has been questioned by police officials say. Earlier, a law enforcement official mistakenly transposed the brothers' first names and mistakenly said Ryan was the shooter.
Chaos struck as children gathered in their classrooms for morning meetings.
Police swarmed the scene and locked down the school, rushing children to safety, some of them bloodied.
Distraught parents converged, frantically searching for their daughters and sons.
Neighbours and friends wandered in shock, looking for information.
''It's hard to believe that anything like this could happen in this town,'' said resident Peter Alpi, 70, as he fought back tears. ''It's a very quiet town. Maybe it's too quiet.''
'EVIL HAS VISITED'
US President Obama has gone on national television to express "overwhelming grief'' at the tragedy.
''Evil visited this community today,'' Connecticut Governor Dannel Malloy told reporters.
"There is not a parent in America who does not feel the same overwhelming grief that I do,'' Obama said.
An emotional Obama said that as a country, the US had been through shootings like this too many times and pledged "meaningful action'' on the issue "regardless of politics''.
"Our hearts are broken today,'' Obama said. He said it was possible the toll could go higher.
Mergim Bajraliu, a 17-year-old high school student, said he was at his home nearby when he heard two shots. He and a neighbour ran to the school to find his 9-year-old sister, Venesa.
"My heart sank," he said, describing seeing two students covered in blood being carried out of the building, one of whom looked like his sister. To his relief, his sister later emerged unharmed, and Bajraliu greeted her with a hug.
"I was like, 'Oh my God," Bajraliu said.
Home to about 27,000 people, the wealthy, wooded town of Newtown is in southeastern Connecticut, about 130 km northeast of New York City.
It is a so-called bedroom community, with many homes situated on multiple acres of land and residents commuting to larger cities including Hartford and Stamford.
"You can never be prepared for this kind of incident," Connecticut Governor Dannel Malloy told reporters. "What has happened, what has transpired at this school building will leave a mark on this community and every family impacted."
ILLUSIONS OF SAFETY SHATTERED
Local churches quickly organised evening memorial services to help residents cope with the trauma that shattered their illusions of safety.
"I don't think you are safe anywhere," said Lori Amaral, who lives about 400 metres from the school. She added that her college-age daughter and her friends were afraid even to go out to the vigil.
"They are afraid to go anywhere," Amaral said.
John Hess was at the airport in Cleveland morning when his wife, Patty, called him to tell him about the shooting. He immediately hopped a plane home to Newtown, where his family moved recently from nearby Stamford.
"We moved here because we thought it would be a safe community," Hess said.
'IN A DAZE'
Parents of children at the school for children aged 5 to 10 years gathered at a fire station down the street from the school building to await news of their children.
Helicopters hovered over the school building and scores of cars were parked on lawns up and down the street, reflecting the hurried response of police, parents and officials after the shooting took place around 9:30am local time (1.30am).
"Everybody was crying," said Alexis Wasik, 8, a third-grader who was in the school when the shooting began. "I was a little scared and felt sick to my stomach."
The attack was the deadliest mass shooting at a US school since a 2007 sniper attack at Virginia Tech left 32 people dead.
"I am still in a daze," said Alexis' mother, Lynn. "My heart is in a million pieces for the children."
Juanita Hall, a school counselor in nearby Ridgefield, whose daughter attends the school, said it would take time for the residents to recover from the shock.
"The most difficult thing is to have a conversation with the children about this. My immediate thoughts were about Columbine," Hall said, referring to a 1999 incident in which students at a Colorado high school killed 13 students and staff.
"It's going to take a very long time for this community to get over this, if it's even possible. I'm not sure it's even possible."
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