Obama: ‘Evil’ Boston bombings were act of terror

"Evil." "Heinous." "Cowardly." President Barack Obama on Tuesday sharply denounced the Boston Marathon bomb attacks even as he held up the heroism of first responders and ordinary Americans in the bloody aftermath of what he labeled "an act of terror."

"The American people refuse to be terrorized. Because what the world saw yesterday in the aftermath of the explosions were stories of heroism and kindness and generosity and love,” the president said in the White House briefing room.

He pointed to exhausted marathon runners who raced to area hospitals to donate blood, others who stayed to help the wounded, some tearing off their own clothes to make tourniquets. He cited first responders “who ran into the chaos to save lives,” medical staff still treating the wounded, religious leaders who tended to the fearful, “and the good people of Boston” who opened their homes.

“If you want to know who we are, what America is, how we respond to evil, that’s it: selflessly, compassionately, unafraid,” Obama said.

"This was a heinous and cowardly act, and given what we now know about what took place, the FBI is investigating it as an act of terrorism," Obama said. "Anytime bombs are used to target innocent civilians, it is an act of terror."

"What we don't yet know, however, is who carried out this attack or why, whether it was planned and executed by a terrorist organization, foreign or domestic, or was the act of a malevolent individual," he said. "Clearly, we are at the beginning of our investigation. It will take time to follow every lead and determine what happened—but we will find out."

"We will find whoever harmed our citizens, and we will bring them to justice."

Obama also ordered American flags flying over government facilities at home and overseas to be lowered to half-staff. Aides lowered the Stars and Stripes fluttering in the overcast Washington sky over the White House and the adjacent Eisenhower Executive Office Building.

The blasts, captured in dramatic videos and photographs, ripped through crowds of onlookers near the race’s finish line. The official toll includes more than 170 wounded, 17 critically, and three fatalities including an 8-year-old boy.

Obama spoke after receiving his latest briefing on the response and investigation from top national security aides including FBI Director Robert Mueller, Attorney General Eric Holder, Homeland Security Secretary Janet Napolitano, and Lisa Monaco, the assistant to the president for homeland security and counterterrorism.