WASHINGTON — A tearful President Barack Obama said Friday he grieved first as a father about the massacre at a Connecticut elementary school, declaring, “Our hearts are broken today.” He called for “meaningful action” to prevent such shootings but did not say what it should be.

“The majority of those who died were children — beautiful, little kids between the ages of 5 and 10 years old,” Obama said.

At that point he had to pause for several seconds to keep his composure, and he wiped his eyes.

The scene in the White House briefing room was one of the most emotional moments of Obama’s presidency. Near him, two senior aides cried and held hands as they listened to the president.

Twenty-seven people, including 20 children, were killed when a gunman opened fire inside the school. The shooter blasted his way through the building as young students cowered helplessly. The dead included the shooter.

The story jolted parents and other people across the nation, and the White House was no different.

Obama began his comments with no greeting. He ended them with words of Scripture, walking away in silence.

He recited the future milestones lost, and had to pause again to gather his words.

“They had their entire lives ahead of them — birthdays, graduations, weddings, kids of their own,” the president said of those who were killed.

He ordered that U.S. flags be flown at half-staff on public grounds through Tuesday. The White House also canceled a trip Obama was planning to take Wednesday to Portland, Maine. Notably, House Speaker John Boehner, with whom Obama is locked in tense budget negotiations, announced that Republicans would not offer their usual Saturday radio address “so that President Obama can speak for the entire nation at this time of mourning.”

The tragedy, like previous ones have, reignited calls from gun control activists for laws restricting access to weapons.

A crowd of about 200 people gathered outside the White House Friday evening for a candlelight vigil, many of them drawn together through social media sites. Speakers urged Obama to push for gun control and said the Connecticut shootings were just the latest in an epidemic of gun violence.

The Rev. Michael McBride of Oakland, Calif., in Washington as part of a religious-based effort to speak out against gun violence, called on Obama to take a stand for gun control before his State of the Union address or during it.

“Platitudes and condolences do not help. We need action,” McBride said.

The president himself signaled a desire for action, but he was not specific.

“As a country, we have been through this too many times,” Obama said. “We’re going to have to come together and take meaningful action to prevent more tragedies like this, regardless of the politics.”

As the president received briefings about the shooting, his spokesman, Jay Carney, responded to questions about gun control and Obama’s campaign promises on the matter by saying “I don’t think today is that day” for such a discussion.

Others, however, said it was.

New York Mayor Michael Bloomberg, an advocate of greater limits on guns, responded directly to the president’s remarks: “Calling for ‘meaningful action’ is not enough. We need immediate action. We have heard all the rhetoric before.”

During Obama’s time in office, mass shootings have shaken communities in Wisconsin, Texas and Colorado.

Obama has called for keeping assault weapons off the streets and the White House has said he still wants Congress to reinstitute a federal ban on military-style assault weapons. But reflecting the difficult politics of gun control, Obama has not pushed for stricter laws, calling for better enforcement of existing laws instead.

The latest attack comes less than two weeks before Christmas. It appeared to be the nation’s second-deadliest school shooting, exceeded only by the Virginia Tech massacre in 2007.

Obama spoke from the “James S. Brady Press Briefing Room,” named in 2000 in honor of the former White House press secretary, James Brady, who was shot and disabled in the assassination attempt on Ronald Reagan in 1981. Brady and his wife, Sarah, have become activists for gun control.

The president and his wife, Michelle, have two daughters.

“Michelle and I will do what I know every parent in America will do, which is hug our children a little tighter,” he said. “But there are families in Connecticut who cannot do that tonight, and they need all us of right now.”

The president pledged support to Connecticut Gov. Dannel P. Malloy.

Said Obama: “He will have every single resource that he needs to investigate this heinous crime.”