(CNN)– President Barack Obama said he ordered the "full resources" of the federal government to respond to the Boston bombings on Monday, and that he also called for increased security around the United States as necessary.
"We still do not know who did this or why," he said from the Brady Press Briefing Room, cautioning people against jumping to conclusions. "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."
Any individuals or groups responsible for the "senseless" bombing, he added, will "feel the full weight of justice."
"The American people will say a prayer for Boston tonight," he said.
Notably absent from his remarks was the word "terror," though federal investigators are classifying the bombings as a terror event. It is not clear if it's from a domestic or foreign source, a federal law enforcement official with knowledge of the investigation said.
Full transcript: Obama reacts to 'senseless' bombings
"Today is a holiday in Massachusetts, Patriot's Day. It's a day that celebrates the free and fiercely independent spirit that this great American city of Boston has reflected from the earliest days of our nation, and it's a day that draws the world to Boston's streets in a spirit of friendly competition," he said. "Boston is a tough and resilient town, so are its people. I'm supremely confident that Bostonians will pull together, 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."
President Barack Obama talks on the phone with FBI Director Robert Mueller to receive an update on the explosions that occurred in Boston, in the Oval Office, April 15, 2013. Seated with the President are Lisa Monaco, Assistant to the President for Homeland Security and Counterterrorism, and Chief of Staff Denis McDonough. (Official White House Photo by Pete Souza)
After Obama's statement, a White House official said "any event with multiple explosive devices – as this appears to be – is clearly an act of terror, and will be approached as an act of terror."
"However, we don’t yet know who carried out this attack, and a thorough investigation will have to determine whether it was planned and carried out by a terrorist group, foreign or domestic," the official continued.
According to the president's Facebook page, an organized call-in event scheduled for Tuesday has been postponed.
"Due to the events at the Boston Marathon, we are postponing tomorrow's National Call Day on gun violence prevention. Our thoughts and prayers are with everyone in Boston," his Facebook stated.
The event, run by the advocacy group Organizing for Action, would have organized supporters to call their senators and urge them to support the current gun legislation bill.
Over on Capitol Hill, House Speaker John Boehner led a moment of silence on the House floor for victims in Boston.
House Speaker John Boehner talks to President Barack Obama on the phone Monday around 5:30 p.m. ET.
And a press conference to roll out the so-called Gang of Eight's immigration plan has also been postponed, according to Democratic Sen. Chuck Schumer of New York.
Vice President Joe Biden, meanwhile, was on a conference call earlier in the day about the Senate legislation to combat gun violence when he heard about the explosions.
"As I'm speaking here, they just turned on the television in my office and apparently there has been a bombing– I don't know any of the details of what caused it, who did it–I don't think it exists yet but our prayers are with those people in Boston who have suffered injuries," he said. "I don't know how many of them there are. I'm looking at it on television now."
- CNN's Tom Cohen, Jessica Yellin and Deirdre Walsh contributed to this report.
We don't have moments of prayer, apparently. We have moments of silence–so as to not offend anyone.
He doesn't know what happned? Isn't the CIA, FBI and Homeland Security supposed to be doing their work to head off this kind of thing? It looks to me to be a failure in Obama's intelligence community. Whatever happened to, "the buck stops here" Mr. Obama?
@ just askin... the real answer is no. It was a state issue until it was declared a "terrorist act".... or National Emergency, Disaster, etc. The President was quick in taking action. Something he and his predecessor were both lack in previously.
Occupy All Streets
@just askin....there is a protocol to emergency assistance from the feds to states and cities; they would have to find out what is needed on site first before sending in just any kind of help. In fact, states have to make a request for help from the feds.....it's called a coordinated response. But I guess when you're looking to criticize something or someone, you can certainly find it.
It may take a while, but they'll find who did this. There were cameras everywhere. Even if they have to go back and trace every individual's steps, they'll see who planted the bombs.
Obama – "Can we get anyone from Newtown to make a plea to stop using these weapons?" – Get the local Police ready to stand behind me when I make a public statement.....
I feel that the timing of this attack–on tax day–may hint that it was carried out by Sovereign Citizens or some other right-wing, anti-tax fringe group.
There shouldn`t be any speculation but let`s remember to include American terrorists in the consideration set. These perps may be more like McVeigh and less like bin Laden. And let`s not let an emotional overreaction lead us into another manufactured war. Irresponsible statements from Congressmen & Senators are not value added [John McCain, Louie Gohmert, Joe Wilson, Mitch McConnell are you listening?
"And we'll find out why they did this"?!#$.... Really? It's because the terrorist, foreign or domestic, who did this hates us. If it domestic, hang the jerk from the highest flagpole. If this was foreign, carpet bomb the source.
Maybe he can pull some of the homeland security saturation team cops away from tru tv's vegas strip show.
Some Americans jump the gun on who did this, it could be any group, lets get the facts first before major assumptions
of course obumma wouldn't admit that.. The war on terror was officially over long time ago...
Lets get the facts first before we assume anything
Thank you CNN for using concentrating on the most INANE aspect of everything and trying to get the GOP sniping at Obama for word choice. At a time of national crisis, you're trying to make sure you make more "news" to cover. Why not try journalism or does that cost too much?
Right... "workplace violence."
Wow...i know I for one feel better.
you can say the "t" word mr. president... be honest with us!
I read they have suspect in custody.
When we figure out who did it, expect a strongly worded letter.
Who cares if he said the word terror?
The media is heartless.
Only the media loves to use words like Terrorism; Catastrophe, etc. to describe things because they are inflammatory words and will inflame emotions resulting in more buying of the media. Presidents are wise to to down play the terror in order to calm the population. What we don't need is a bunch of people thrown into emotional instability by inflammatory words and gestures.
This is likely alQaida's payback to US hitting some of their leaders. But Ayman Al Zawahiri, bin Laden's top man is still out there 12 years after 9/11. If Obama doesn't get him – all his words of "justice" would be in vane.
Okay Obama, You ignored the Benghazi bombings, but you can't ignore this one!
Why not we put cameras all over big cities like Boston, NY, LA etc. very sad.