President Barack Obama on Saturday marked the anniversary of the shooting of 26 people at the Newtown school in Connecticut by urging Americans to press for gun law changes to prevent similar dramas.
"One year ago today, a quiet, peaceful town was shattered by unspeakable violence," Obama said in his weekly radio address.
Six school workers and 20 children at Sandy Hook Elementary school "were taken from our lives forever," he said.
"But beneath the sadness, we also felt a sense of resolve – that these tragedies must end, and that to end them, we must change."
On December 14, 2012, a heavily armed man identified as 20-year-old Adam Lanza entered the school and opened fire. In ten minutes he shot and killed 26 people before taking his own life.
The senseless slaughter of young children at the hands of a mentally disturbed individual shook the nation's conscience like no other mass shooting in years.
"We have to do more to keep dangerous people from getting their hands on a gun so easily," said Obama.
"We have to do more to heal troubled minds. We have to do everything we can to protect our children from harm and make them feel loved, and valued, and cared for."
Obama also emphasized that "we can’t lose sight of the fact that real change won’t come from Washington. It will come the way it’s always come -– from you. From the American people."
At 9:25 am the president and his wife Michelle will observe a moment of silence at the White House and light candles in memory of the Sandy Hook victims, officials said.
The Newtown massacre relaunched a push for gun control laws, and a handful of states have since tightened gun rules.
But the nationwide measures the president supported failed in the US Senate in April due to fierce opposition from gun rights supporters.
On Friday, the eve of the Sandy Hook slaughter, a schoolboy in Colorado armed with a shotgun opened fire at his high school and wounded two fellow students -- one critically -- before killing himself.
The Arapahoe High School shooting took place a few miles from the sites of last year's Aurora cinema shooting, where 12 people were killed and scores wounded during a Batman movie, and the 1999 Columbine High School bloodbath, where 13 were killed as well as the two student gunmen.