President Barack Obama said the nation was grieving for those killed during the "tragic shooting" in Newtown, Connecticut.
During his weekly radio and television address, the President said, "We have endured far too many of these tragedies in the last few years ... We have to come together and take meaningful action to prevent more tragedies like this. Regardless of the politics".
More top news
A Russian tourist has been fined 20 Euros (£15,829) for engraving a 10-inch tall letter 'K' on a wall of the Colosseum in Rome with a stone.
Ex-minister Owen Paterson said David Cameron should apply to leave the EU immediately after the general election next year.
Fresh data revealed smartphone and tablet users are increasingly targeted by online crooks.