President Barack Obama has spoken out on gun control on the anniversary of the Sandy Hook massacre, when 27 people were killed by high school gunman Adam Lanza in Connecticut.
"We haven't yet done enough to make our communities and our country safer," Obama said. "We have to do more to keep dangerous people from getting their hands on a gun so easily. We have to do more to heal troubled minds."
The president, whose address was pre-recorded, did not refer to the shooting at a Colorado high school which left one female student in critical condition.
Obama is due to observe a moment of silence at the White House today in memory of those who died at Sandy Hook.
Earlier this year the US Senate blocked new laws that would have made it harder for Americans to buy certain types of weapons.
Today is the first anniversary of the US Sandy Hook school massacre, in which 27 people died at the hands of 20-year-old Adam Lanza.
Residents of Newton, Connecticut, will mark the date quietly, without any public memorials, and have urged others to honour the victims with random acts of kindness.
The anniversary comes a day after a student shot and wounded pupils at a high school in Colorado before shooting himself dead at the scene.
A year after the massacre at Sandy Hook Elementary School shocked the world, little has changed in how America thinks about guns.Read the full story ›
In one recording released by US authorities, a teacher at Sandy Hook Elementary School tells emergency operators she has heard shooting.
"It sounds like there are gunshots in the hallway. I'm a teacher at the school," she says.
"Keep everybody calm, get everybody away from the windows," she is told. "Try to lock down the school, OK?"
A court order has forced the publication of recordings of emergency calls made to police during the Sandy Hook school shootings in Connecticut, USA, last year.
Operators can be heard responding to witnesses including a teacher and a caretaker who report hearing gunshots.
Prosecutors had tried to block the release of the audio files but a legal challenge from the Associated Press news agency ensured the recordings were made public.
Former pupil Adam Lanza, 20, fatally shot 20 schoolchildren, six members of staff, his mother and himself on 14th December 2012.
Police in the United States made clear this evening that families of the 26 victims of the Sandy Hook school gunman will never know why he shot them.
The family of Victoria Soto, a teacher who shielded her students before being shot to death by Adam Lanza, said the release of the report into the massacre is "yet another blow that our family has been dealt."
"While others search for the answer as to why this happened, we search for the how. How can we live without Vicki? How do we celebrate Christmas without Vicki? Those are the questions we seek the answers for. There is nothing in the report that will answer those for us," the family statement said.
Pictures from inside the Sandy Hook Elementary School released by Connecticut authorities show how Adam Lanza shot his way into the school building through a glass window.
He went on to kill 26 people, including 20 children.
Adam Lanza kept violent video games and articles describing various mass-shootings in his bedroom, the report into the Sandy Hook massacre revealed.
Previously unseen images from inside the gunman's home show more guns and ammunition as well as edged weapons, knives, swords and spears. The photographs also show Lanza's bedroom windows taped over with black bin bags.