"We needed this," said the Rev. Matt Crebbin, senior minister of the Newtown Congregational Church. "We needed to be together to show that we are together and united."
Obama told Connecticut Gov. Dannel Malloy that Friday was the most difficult day of his presidency. The president has two daughters, Malia and Sasha, who are 14 and 11, respectively.
"Can we say that we're truly doing enough to give all the children of this country the chance they deserve to live out their lives in happiness and with purpose? I've been reflecting on this the last few days," the president said, somber and steady in his voice. "And if we're honest with ourselves, the answer is no. We're not doing enough and we will have to change."
He promised in the coming weeks to talk with law enforcement, mental health professionals, parents and educators on an effort to prevent mass shootings.
The shootings have restarted a debate in Washington about what politicians can to do help — gun control or otherwise. Obama has called for "meaningful action" to prevent killings.
Police say the gunman, Adam Lanza, was carrying an arsenal of ammunition big enough to kill just about every student in the school if given enough time. He shot himself in the head just as he heard police drawing near, authorities said.
A Connecticut official said the gunman's mother was found dead in her pajamas in bed, shot four times in the head with a.22-caliber rifle. The killer then went to the school with guns he took from his mother and began blasting his way through the building.
"There is no blame to be laid on us but there is a great burden and a great challenge that we emerge whole," First Select Woman Patricia Llodra said. "It is a defining moment for our town, but it does not define us."
Obama said his words of comfort would not be enough, but he brought them anyway, on behalf of parents everywhere now holding their children tighter.
"I can only hope that it helps for you to know," he said, "that you are not alone in your grief."
Associated Press writers David Klepper in Newtown and Julie Pace and Kevin Freking in Washington contributed to this report.
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