President Barack Obama speaks in the James Brady Press Briefing Room at the White House in Washington, Monday, April 15, 2013, following the explosions at the Boston Marathon.National Journal

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President Obama pledged to bring "the full weight of justice" to bear on those who detonated the bombs that brought death and injury to the Boston Marathon Monday. But he stopped short of calling it a terrorist attack, urging patience as the investigation proceeds on both the federal and local levels.

"We still do not know who did this or why," the president said in a somber three-minute appearance in the White House briefing room shortly after 6 p.m. "And people shouldn't jump to conclusions before we have all of the facts. But make no mistake. We will get to the bottom of this and we will find out who did this. We'll find out why they did this."

His comments came after an afternoon in which he was briefed several times on developments. He talked with his top Homeland Security Adviser Lisa Monaco and other members of his senior staff, according to the White House. He then telephoned Boston Mayor Tom Menino and Massachusetts Gov. Deval Patrick "to make sure that they have every single federal resource necessary" and to reassure them "that all Americans stand with the people of Boston."

Later in the afternoon, Obama was briefed again by FBI Director Robert Mueller and Department of Homeland Security Secretary Janet Napolitano on what the White House for the first time was calling an "active investigation."  The briefings covered the needed federal response and "ongoing coordination with state and local officials."

He also talked with top congressional leaders. At a time of intense partisanship, he said he and the leaders "reaffirmed that on days like this, there are no Republicans or Democrats. We are Americans united in concern for our fellow citizens."

Despite the president's caution, there were reports that the FBI has already concluded the attack was a case of terrorism, though it was unknown if the perpetrators were domestic or foreign. "We don't yet have all the answers," said Obama. "But we do know that multiple people have been wounded, some gravely, in explosions at the Boston Marathon."

He praised the swift response of Boston's firefighters and police and the National Guard troops on the scene. "We salute all those who assisted in responding so quickly and professionally to this tragedy," he said. He assured Bostonians that the country will not forget them.

"Boston is a tough and resilient town. So are its people," he said. "I'm supremely confident that Bostonians will ... take care of each other and move forward as one proud city and as they do, the American people will be with them every single step of the way." And he promised again that the investigation will uncover those who planted the bombs. "We will find out who did this and we will hold them accountable."

In the wake of the bombing, security was increased around the White House, with the Secret Service restricting pedestrian access on Pennsylvania Avenue. CBS News also reported that the Air Force has dispatched planes to Boston to control the air space above the city.

Despite the incident, the president maintained his schedule, participating in a ceremony in the Oval Office, accepting the credentials of foreign ambassadors new to Washington.

This article is from the archive of our partner National Journal.

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