Washington, D.C., and Massachusetts have taken a break from politics as usual this week, in the wake of the Boston Marathon bombings Monday.
All five candidates in the race for a Massachusetts' seat in the U.S. Senate suspended their campaigns for the week.
Washington lawmakers put off public events tied to two hot-button issues of the day -- immigration and gun control -- but continued to work behind the scenes on both.
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The Senate "Gang of Eight" still intended to release their plan for immigration overhaul today, but without the fanfare typically associated with an agreement anticipated for months. The senators canceled a news conference that would have represented an opportunity for them to sell the bill to the American people.
Rep. Steve King, R-Iowa, today argued for holding off on immigration overhaul, citing the investigation of the explosions in Boston that included interest in a 20-year-old Saudi national.
"We need to be ever vigilant," King told the National Review. "We need to go far deeper into our border crossings. ... We need to take a look at the visa-waiver program and wonder what we're doing."
House Speaker John Boehner called it "a terrible day for all Americans" but expressed optimism in remarks to the media today that the country will come together.
"I don't think words can express our sorrow for the families that are grieving today as a result of what happened in Boston," the Ohio Republican said. "The whole House yesterday offered our moment of silence but our whole House continues to pray for the victims and their families."
Boehner went on to predict that authorities will find out who was responsible for what he called "a terrorist attack."
"Obviously, we want to know who did this and why was it done," Boehner told reporters this morning. "We don't know who perpetrated this or for what reasons but I'm confident that we'll get to the bottom of it."
Today was also expected to be a big day in the gun control debate, as advocates and opponents gear up for a vote later this week on the background-check provision agreed upon by Sens. Joe Manchin, D-W.Va., and Pat Toomey, R-Pa. The vote was to be delayed until Thursday or possibly early next week, unrelated to events in Boston, Senate aides told ABC News Monday night.
The group that grew out of the Obama campaign, Organizing for Action, was scheduled to hold a "national call day" today, asking supporters to call their senators about gun control measures. It was cancelled Monday night.
"Due to the events at the Boston Marathon today, we are postponing tomorrow's National Call Day on gun violence prevention. We'll update you when we know more about what's next in this effort," a post on OFA's website read. "Please join us in keeping Boston in your thoughts and prayers."
But many in the Capitol were still hard at work on gun-control measures.
Sens. Toomey and Manchin held a private meeting with former Arizona congresswoman Gabrielle Giffords and her husband, Mark Kelly, who have argued on behalf of gun-control legislation in recent months. The two were on the Hill for a dedication ceremony in the U.S. Capitol Visitor Center where a plaque was set to be unveiled honoring Gabe Zimmerman, Giffords' aide who was killed in the Tucson, Ariz., shootings in 2011.
Congress Offers Prayers for Boston
Both the House and Senate opened their sessions today with prayers for the victims and survivors in Boston.
"The explosions at the Boston marathon remind us that we live in a dangerous world and that human life, regardless of the level of physical excellence, is fragile," Senate Chaplain Barry Black prayed on the Senate floor this morning. "Use our lawmakers as instruments of your providence. May they labor with such faithfulness and integrity that you will surround them and our nation with the shield of your favor."
Senate Majority Leader Reid, D-Nev., said the Senate is "still reeling" from the "senseless violence" at Monday's marathon.
"Adding to the horror of this tragedy are the questions of who did this and why," Reid said. "The Federal Bureau of Investigation, Department of Homeland Security investigating this attack as aggressively as possible. As the president said last night, rest assured that the perpetrators will feel the full weight of justice for this terrible crime."
Senate Minority Leader Mitch McConnell, R-Ky., called the attack an "act of terror."
"Those responsible for this act of terror will be brought to justice for their deeds, but today our thoughts are mainly with the victims, their families, and friends," McConnell said. "These horrific attacks are a grim reminder of the hatred and contempt that many continue to harbor in their hearts not only for our nation and its freedoms, but for innocent human life."
Members of Congress and other politicians expressed their condolences through social media platforms like Facebook and Twitter.
Rep. Kyrsten Sinema, D-Ariz., tweeted several times in the course of four hours after the explosions.
"Horrible news about explosions, injuries at Boston Marathon finish. Hoping everyone is ok," she tweeted around 4 p.m. Monday.