President Obama on Saturday marked the one-year anniversary of the mass shooting at an elementary school in Newtown, Conn., and said the nation has not “done enough” to stop gun violence.

“One year ago today, a quiet, peaceful town was shattered by unspeakable violence,” said Obama in his weekly address. “Six dedicated school workers and 20 beautiful children were taken from our lives forever.

“But beneath the sadness, we also felt a sense of resolve – that these tragedies must end, and that to end them, we must change,” he added.

Twenty children and six adults were killed in a shooting rampage at Sandy Hook Elementary School in 2012. The violence shocked the nation and spurred a new debate over gun control.

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