A picture released by the White House captures the moment Barack Obama was told of Sandy Hook shootings, a day he has described as "the worst of his presidency."
Eyes closed, head bowed, Obama is briefed on details of how gunman Adam Lanza killed 20 children, all first graders aged six or seven, who were shot up to 11 times each.
The distress etched on his face was felt by millions around the world as the tragedy hit international headlines.
The President reacts as John Brennan, his deputy national security adviser briefs him
As the events of the cold December day unfolded, the death toll mounted, with Lanza also killing six women, including school headmistress Dawn Hochsprung, before turning the gun on himself. His mother Nancy was found shot dead at their home in the town.
The shooting has reignited fierce debate around America's gun control laws and Obama has ask his deputy Joe Biden to lead a team tasked with delivering "concrete" gun control proposals by January.
"This time the words need to lead to action," Obama told a White House press briefing in December.
"We may never know all the reasons why the [Sandy Hook] tragedy happened, but we do know everyday since, more Americans have died from gun violence.
"If there is even one thing we can do to prevent these events, we all of us have an obligation to try.
"We need to reduce the epidemic of gun violence that plagues this country every single day."