With a flash of fire and a pair of deafening blasts, the Boston Marathon disintegrated Monday into a bloody scene of chaos and terror after two bombs went off near the finish line of the iconic race, killing at least three, severing limbs, injuring more than 130 and setting the country on high alert.
In scenes reminiscent of 9/11, video cameras captured gripping footage of bloodied bystanders running from the bomb sites as police and emergency responders made their way through the smoke to the injured.
Authorities had no suspects in custody, and officials in Washington said there was no immediate claim of responsibility. The Wall Street Journal reported later that as many as five additional undetonated bombs were found after the attack.
President Obama went before TV cameras shortly after 6 p.m. and vowed that those responsible would “feel the full weight of justice.”
The explosions occurred less than a minute apart, shortly before 3 p.m., along the north side of Boylston Street, knocking runners and bystanders to the ground.
Various media outlets reported that an 8-year-old was among those killed. Hospitals reported 134 injured, many of them missing limbs and 15 in critical condition.
Emergency responders flooded the area, breaking through makeshift fencing and national flags that were set up to adorn the race, while medical staff on hand to treat exhausted runners were conscripted into much more serious duties.
The attack immediately brought to mind the makeshift bombs normally associated with the Middle East. Officials in New York City and Washington heightened security on their streets and transit systems, while officials in London took stock of their security plans ahead of a marathon there Sunday.
The timing of the attack may have been intended to maximize casualties: The race leaders are long gone, but thousands of recreational runners, along with their cheering families and supporters, traditionally crowd the finish line at the four-hour mark.
In Boston, police Commissioner Edward Davis asked people to stay home or in their hotels.
After the explosions, witnesses said, they saw many people falling to the ground with bloody injuries from what one man described as a shrapnel-type bomb that erupted from the sidewalk.
“It didn’t come from the street, it didn’t come from a manhole,” the onlooker told NBC News.
A White House official said FBI Director Robert S. Mueller III and Homeland Security Secretary Janet A. Napolitano briefed Mr. Obama on the investigation and response to the explosions, including coordination among federal agencies and state and local officials.
Mr. Obama directed his administration to provide whatever assistance is necessary in the investigation and response.
“Our prayers are with those people in Boston who have suffered injuries. I don’t know how many there are,” Vice President Joseph R. Biden said.
An analyst warned that the explosions were likely terrorist bombs and more could be coming.
“The apparent Boston Marathon bombings are likely a terrorist attack,” said Ben Venzke of private-sector intelligence outfit IntelCenter.
Law enforcement sources told NBC that the first of two explosions appeared to be caused by a small homemade bomb, perhaps hidden in a mailbox. The second explosion also makes it likelier that both were deliberate.
Mr. Venzke said he was closely monitoring extremist websites and chat rooms for any claim of responsibility or threat of further attacks.
“No credible claims have been identified so far,” he said, but if the perpetrators were a properly organized and experienced terrorist group, “there is the distinct possibility of additional coordinated attacks in Boston and/or other major cities.”
Sen. Dianne Feinstein, California Democrat and head of the Senate Select Committee on Intelligence, shot down news reports that said police were holding a Saudi national in connection with the explosions.
Reminiscent of 9/11
Across the country, viewers who tuned into daytime TV programming such as the “Ellen DeGeneres Show” and “The Dr. Oz Show” were greeted instead by urgent special reports on what had happened at the race — one of the city’s biggest events, held each year on Patriots Day, which commemorates the first battles of the American Revolution, at Concord and Lexington in 1775.
Competitors and race organizers were crying as they fled the chaos. Bloody spectators were carried to the medical tent that had been set up to care for fatigued runners.
Ryan Stevenson, 29, who lives outside the city, said he found out about the blast shortly before leaving work to walk to the North Station transportation hub.
“But even if I hadn’t heard, you could tell that something was wrong on people’s faces,” he said in an email to The Washington Times. “Runners wearing their medals looked distant to me. Parents holding their children had a sickened expression on their face.”
Police scanners lit up with crosstalk about suspicious packages and what to do with personal effects the runners had to leave behind, while pro hockey officials postponed a game in Boston between the Ottawa Senators and hometown Bruins.
Initial reports of a third explosion at the John F. Kennedy Presidential Library and Museum were investigated, though later reports suggested it was an unrelated fire at the building.
Massachusetts Gov. Deval Patrick said Mr. Obama assured him that the state would have the full cooperation of the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives.
The Senate observed a moment of silence for the victims just before an evening vote, and Speaker John A. Boehner, Ohio Republican, led a moment of silence in the House later Monday.
“It’s just a sad, horrific occasion that Boston’s experiencing today,” Sen. William M. Cowan, Massachusetts Democrat, said from the Capitol.
In Washington, crowds near the White House were pushed back to Lafayette Park with the Secret Service shutting down Pennsylvania Avenue during the peak of the spring tourism season.
In an abundance of caution, the Metro transit system beefed up its police presence through at least the Tuesday evening rush hour, said agency spokesman Dan Stessel.
“We’ll have additional police presence on the system until we have better assessment of what has happened in Boston,” he said, adding that there were no reports of specific or credible threats against the system.
⦁ Shaun Waterman, Susan Crabtree and Stephen Dinan contributed to this report.