school shooting leaves 27 dead,
Connecticut elementary school shooting leaves 27 dead, including 20 children
Twenty children and six adults have been killed in a shooting attack at a primary school in the US state of Connecticut, police say.
Police Lt Paul Vance said the gunman was also dead, but gave no cause.
US media said the gunman at Sandy Hook Elementary School, Newtown, as Ryan Lanza, 24, said to be from New Jersey, but police gave no confirmation.
The killings make Newtown the second-worst US shooting, after 32 died at Virginia Tech in 2007.
Friday's shooting is the third major gun attack in the US in 2012.
In July an attacker killed 12 people at a premiere of a Batman film in Aurora, Colorado. In August six people died at a Sikh temple in Wisconsin.
Just this week two people died in a shooting at mall in the state of Oregon.
At the White House, an emotional President Barack Obama cited those incidents as he called for "meaningful action... regardless of politics".
"Our hearts are broken today, for the parents, grandparents, sisters and brothers of these children, and for the families of the adults who were lost."
Mr Obama offered condolences to the families of survivors too, saying "their children's innocence has been torn away from them too early, and there are no words that will ease their pain".
He wiped tears from his eyes as he spoke of the "overwhelming grief" at the loss of life.
The American flags on Capitol Hill in Washington DC have been lowered to half-mast in the wake of the attack.
Sandy Hook School - described by correspondents as a highly rated school has more than 600 students in from Kindergarten to 4th Grade - spanning the ages five to 10.
Lt Vance said 18 children were pronounced dead at the school, and two died after they were taken to hospital. Six adults were also killed. The gunman died at the scene.
The attack took place in two rooms within a single section of the school, he said.
One person was also injured in the attack, Lt Vance added.
Police said there was another victim at a second crime scene, but did not provide details.
Police arrived at the school soon after 09:40 local time (14:40 GMT), answering reports that a gunman was in the school's main office and one person had "numerous gunshot wounds".
Scores of officers at the scene carried out a full search of the site. Classes were cancelled as the situation developed.
schools across the district were immediately on lock-down as a preventive measure, officials said.
According to US reports, the gunman's mom was a teacher found among the dead at the school. The Associated Press said his brother was being held by police.
The attacker was dressed in black and wearing a bullet-proof vest during the attack, and reportedly used a .223-calibre rifle. Other weapons are also said to have been recovered.
With the death toll rising, it emerged that one entire classroom of students may remain unaccounted for, local sources reported.
Three other people were taken to hospital and are reported to be in "very serious condition", Danbury Mayor Mark Boughton told CNN.
One witness speaking to CNN said that shots were heard coming from the hall. There "must have been 100 rounds" fired, she told the channel.
Local media have reported that firefighters instructed children to close their eyes and run past the school's office as they exited the building.
Other sources suggest that some of the shots were fired in a school classroom.
There were early unconfirmed reports of two shooters, but no further details of a second gunman mentioned by police.
With the children now evacuated, aerial images of the school show emergency vehicles still at the scene and scores of cars surrounding the area.
Parents and children were seen weeping and comforting friends and family at the school as the scale of the shooting gradually became clear. Officials say they are trying to unite children with their parents.