BOSTON (AP) — Two bombs exploded in the crowded streets near the finish line of the Boston Marathon on Monday, killing at least three people and injuring more than 140 in a bloody scene of shattered glass and severed limbs that raised alarms that terrorists might have struck again in the U.S.
A White House official speaking on condition of anonymity because the investigation was still unfolding said the attack was being treated as an act of terrorism.
President Barack Obama vowed that those responsible will "feel the full weight of justice."
As many as two unexploded bombs were also found near the end of the 26.2-mile course as part of what appeared to be a well-coordinated attack, but they were safely disarmed, according to a senior U.S. intelligence official, who also spoke on condition of anonymity because of the continuing investigation.
The fiery twin blasts took place about 10 seconds and about 100 yards apart, knocking spectators and at least one runner off their feet, shattering windows and sending dense plumes of smoke rising over the street and through the fluttering national flags lining the route. Blood stained the pavement, and huge shards were missing from window panes as high as three stories.
"They just started bringing people in with no limbs," said runner Tim Davey of Richmond, Va. He said he and his wife, Lisa, tried to shield their children's eyes from the gruesome scene inside a medical tent that had been set up to care for fatigued runners, but "they saw a lot."
"They just kept filling up with more and more casualties," Lisa Davey said. "Most everybody was conscious. They were very dazed."
As the FBI took charge of the investigation, authorities shed no light on a motive or who may have carried out the bombings, and police said they had no suspects in custody. Officials in Washington said there was no immediate claim of responsibility.
WBZ-TV reported late Monday that law enforcement officers were searching an apartment in the Boston suburb of Revere. Massachusetts State Police confirmed that a search warrant related to the investigation into the explosions was served Monday night in Revere but provided no further details.
Police said three people were killed. An 8-year-old boy was among the dead, according to a person who talked to a friend of the family and spoke on condition of anonymity. The person said the boy's mother and sister were also injured as they waited for his father to finish the race.
Hospitals reported at least 144 people injured, at least 17 of them critically. The victims' injuries included broken bones, shrapnel wounds and ruptured eardrums.
At Massachusetts General Hospital, Alisdair Conn, chief of emergency services, said: "This is something I've never seen in my 25 years here ... this amount of carnage in the civilian population. This is what we expect from war."
Some 23,000 runners took part in the race, one of the world's oldest and most prestigious marathons.
One of Boston's biggest annual events, the race winds up near Copley Square, not far from the landmark Prudential Center and the Boston Public Library. It is held on Patriots Day, which commemorates the first battles of the American Revolution, at Concord and Lexington in 1775.
Boston Police Commissioner Edward Davis asked people to stay indoors or go back to their hotel rooms and avoid crowds as bomb squads methodically checked parcels and bags left along the race route. He said investigators didn't know whether the bombs were hidden in mailboxes or trash cans.
He said authorities had received "no specific intelligence that anything was going to happen" at the race.
The Federal Aviation Administration barred low-flying aircraft within 3.5 miles of the site.
"We still don't know who did this or why," Obama said at the White House, adding, "Make no mistake: We will get to the bottom of this."
With scant official information to guide them, members of Congress said there was little or no doubt it was an act of terrorism.
"We just don't know whether it's foreign or domestic," said Rep. Michael McCaul, R-Texas, chairman of the House Committee on Homeland Security.
A few miles away from the finish line and around the same time, a fire broke out at the John F. Kennedy Library. The police commissioner said that it may have been caused by an incendiary device but that it was not clear whether it was related to the bombings.
The first explosion occurred on the north side of Boylston Street, just before the finish line, and some people initially thought it was a celebratory cannon blast.
When the second bomb went off, spectators' cheers turned to screams. As sirens blared, emergency workers and National Guardsmen who had been assigned to the race for crowd control began climbing over and tearing down temporary fences to get to the blast site.
The bombings occurred about four hours into the race and two hours after the men's winner crossed the finish line. By that point, more than 17,000 of the athletes had finished the marathon, but thousands more were still running.
The attack may have been timed for maximum carnage: The four-hour mark is typically a crowded time near the finish line because of the slow-but-steady recreational runners completing the race and because of all the friends and relatives clustered around to cheer them on.
Runners in the medical tent for treatment of dehydration or other race-related ills were pushed out to make room for victims of the bombing.
A woman who was a few feet from the second bomb, Brighid Wall, 35, of Duxbury, said that when it exploded, runners and spectators froze, unsure of what to do. Her husband threw their children to the ground, lay on top of them and another man lay on top of them and said, "Don't get up, don't get up."
After a minute or so without another explosion, Wall said, she and her family headed to a Starbucks and out the back door through an alley. Around them, the windows of the bars and restaurants were blown out.
She said she saw six to eight people bleeding profusely, including one man who was kneeling, dazed, with blood trickling down his head. Another person was on the ground covered in blood and not moving.
"My ears are zinging. Their ears are zinging," Wall said. "It was so forceful. It knocked us to the ground."
Competitors and race volunteers were crying as they fled the chaos. Authorities went onto the course to carry away the injured, while race stragglers were rerouted away from the smoking site.
Roupen Bastajian, a state trooper from Smithfield, R.I., had just finished the race when he heard the blasts.
"I started running toward the blast. And there were people all over the floor," he said. "We started grabbing tourniquets and started tying legs. A lot of people amputated. ... At least 25 to 30 people have at least one leg missing, or an ankle missing, or two legs missing."
The race honored the victims of the Newtown, Conn., shooting with a special mile marker in Monday's race.
Boston Athletic Association president Joanne Flaminio previously said there was "special significance" to the fact that the race is 26.2 miles long and 26 people died at Sandy Hook Elementary School.
Associated Press writers Jay Lindsay, Steve LeBlanc, Bridget Murphy and Meghan Barr in Boston; Julie Pace, Lara Jakes and Eileen Sullivan in Washington; and Marilynn Marchione in Milwaukee contributed to this report.
Follow @WUFTNews for the latest updates.
Updated 11:56 p.m. BOSTON (AP) — A television station is reporting that police are searching an apartment in a Boston suburb, and authorities confirm the search is part of the investigation into the explosions near the finish line of the Boston Marathon.
WBZ-TV reports that police are searching the apartment in Revere. Massachusetts State Police confirmed that a search warrant was served Monday night but provided no further details.
The FBI is leading the investigation into the explosions, which killed three people and injured more than 140 others.
https://twitter.com/BostonGlobe/status/324010238036566016
Updated 8:57 p.m. BOSTON (AP) — Police say at least three people have been killed in the explosions near the finish line of the Boston Marathon.
Police commissioner Ed Davis confirmed the three deaths but provided no details.
The explosions Monday also injured more than 130 people, knocking spectators and at least one runner off their feet.
Some of the victims lost arms and legs. Other injuries included broken bones, shrapnel wounds and ruptured eardrums.
http://www.youtube.com/watch?v=ZBkPFRY9VTY&feature=youtu.be
https://twitter.com/cnnbrk/status/323962845173796864
Updated 8 p.m.: BOSTON (AP) — Authorities say bombs that exploded near the finish line of the Boston Marathon have killed two people and injured more than 120.
Eight hospitals report that they are treating at least 124 people. Of those, at least 15 are in critical condition.
The injuries ranged from cuts and bruises to amputations. Many victims suffered lower leg injuries and shrapnel wounds. Some suffered ruptured eardrums.
Dr. Richard Wolfe, chief of the department of emergency medicine at Beth Israel Deaconess Medical Center, says one or two of the hospital's 21 patients faced a "high probability of mortality."
Updated 6:44 p.m.: WASHINGTON (AP) — President Barack Obama, responding to the explosions at the Boston Marathon, says the United States does not know "who did this or why" but vowed that whoever is responsible "will feel the full weight of justice."
He said: "We will find out who did this and we will hold them accountable."
Obama made his remarks Monday evening from the White House about three hours after two explosions detonated near the marathon's finish line. At least two people were killed and 50 injured in the blasts.
Obama has been in touch with federal law enforcement and Massachusetts officials in the aftermath of the explosions.
The Secret Service reacted cautiously to the blasts, expanding the security perimeter around the White House.
http://www.youtube.com/watch?feature=player_embedded&v=4x-VKqe4cvA
Updated 5:47 p.m.: President Obama to address Boston Marathon explosions at 6:10 p.m.
Updated 5:44 p.m.: Boston Globe reporting at least 90 people injured, according to area hospitals.
https://twitter.com/BostonGlobe/status/323914331941117952
Updated 5:27 p.m.: Boston Police says JFK library incident is related to fire, not explosion.
https://twitter.com/Boston_Police/status/323909232195944449
Updated 5:22 p.m.: Full audio below from Mike Gillespie and his phone interview with former Gainesville resident and UF alumnus Matt Hensley.
Updated 5:13 p.m.: Google launches person finder for Boston Marathon explosions.
http://google.org/personfinder/2013-boston-explosions/
Updated 5:10 p.m.: Boston Globe reporting that more than 100 people are being treated at hospitals.
https://twitter.com/BostonGlobe/status/323905300568608770
Updated 5:07 p.m.: Associated Press reporting that cell phone service in Boston has been shut down to prevent remote detonations of explosives. If looking for family members, phone number to call is 617-635-4500. To report information: 800-494-TIPS.
Updated 4:52 p.m.: The New York Times released a map that details where the explosions happened.
Updated 4:44 p.m.: Reuters reporting third explosion at JFK Library.
https://twitter.com/ReutersUS/status/323896463321079811
Updated 4:34 p.m.: There were 591 runners from Florida at the Boston Marathon, 20 were from Gainesville.
Updated 4:29 p.m.: Two former Gator runners who ran in the Boston Marathon, Matt Hensley, 25, and Jeremy Criscione, 25, are fine.
Amanda Brooks, Florida Track and Field spokeswoman, spoke to the two men and said everyone was safe.
Hensley's brother, Jeff, a former Gator, said he and his family had gone back to an apartment before the explosions occurred.
"It turned such a good day into such a bad one," Jeff Hensley said.
No current Gator runners participated in the marathon, Brooks said.
Updated 4:24 p.m.: Intelligence official: 2 more explosive devices found at Boston Marathon are being dismantled.
Updated 4:08 p.m.: Boston Police Department says two dead, 23 injured.
Updated 3:58 p.m.: The White House says President Barack Obama has been notified about the explosions at the finish line of the Boston Marathon.
The White House says the administration is in contact with state and local authorities and directed his administration to provide whatever assistance is necessary in the investigation and response.
Vice President Joe Biden was on a conference call with gun control activists when staffers turned on televisions in his office Monday to view coverage of the explosions. Biden said during the call that his prayers were with those who suffered injuries.
Original story: BOSTON (AP) — Two explosions shattered the finish of the Boston Marathon on Monday, sending authorities out on the course to carry away the injured while stragglers in the 26.2-mile race were rerouted away from the smoking site.
Competitors and race volunteers were crying as they fled the chaos. Bloody spectators were being carried to the medical tent that had been set up to care for fatigued runners.
"There are a lot of people down," said one man, whose bib No. 17528 identified him as Frank Deruyter of North Carolina. He was not injured, but marathon workers were carrying one woman, who did not appear to be a runner, to the medical area as blood gushed from her leg. A Boston police officer was wheeled from the course with a leg injury that was bleeding.
Neither race officials nor public officials could immediately estimate the number or degree of injuries.
About three hours after the winners crossed the line, there was a loud explosion on the north side of Boylston Street, just before the photo bridge that marks the finish line. Another explosion could be heard a few seconds later.
Smoke rose from the blasts, fluttering through the national flags lining the route of the world's oldest and most prestigious marathon. TV helicopter footage showed blood staining the pavement in the popular shopping and tourist area known as the Back Bay.
"There are people who are really, really bloody," said Laura McLean, a runner from Toronto, who was in the medical tent being treated for dehydration when she was pulled out to make room for victims of the explosions. "They were pulling them into the medical tent."
Cherie Falgoust was waiting for her husband, who was running the race.
"I was expecting my husband any minute," she said. "I don't know what this building is ... it just blew. Just a big bomb, a loud boom, and then glass everywhere. Something hit my head. I don't know what it was. I just ducked."
Runners who had not finished the race were diverted straight down Commonwealth Avenue and into a family meeting area, according to an emergency plan that had been in place.
Two explosions went off near the finish line at the Boston Marathon, injuring at least six people.
Correction appended: a previous version of this story said Matt Hensley was a Gainesville resident. He no longer lives here, but is a UF alumnus.
http://storify.com/wuftnews/explosions-rock-boston-marathon