The simultaneous explosions, and reports of two other unexploded devices found near the scene raised suspicions that the blasts, just before 3 p.m., could be part of a terrorist attack. Intelligence officials told The Associated Press two unexploded devices were being dismantled, and reports of a third "controlled" explosion near the JFK Library in the Columbia Point section of Dorchester, may have been an intentional detonation supervised by authorities. Competitors and race organizers were crying as they fled the bloody chaos, while some witnesses reported seeing victims with lost limbs.
"Somebody's leg flew by my head," a spectator, who gave his name as John Ross, told the Boston Herald. “I gave my belt to stop the blood.”
Witnesses heard booms that sounded like two claps of thunder near the finish line inside the Fairmount Copley Plaza Hotel, according to multiple local reports.
Video of the scene showed a number of emergency crews in the area tending to victims and blood on the ground near the finish line.
"I saw two explosions. The first one was beyond the finish line. I heard a loud bang and I saw smoke rising," Boston Herald reporter Chris Cassidy, who was running in the marathon, told the newspaper. "I kept running and I heard behind me a loud bang. It looked like it was in a trash can or something...There are people who have been hit with debris, people with bloody foreheads.”
"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.
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 thunderous explosion could be heard a few seconds later.
Runner Laura McLean of Toronto said she heard two explosions outside the medical tent.
"There are people who are really, really bloody," McLean said. "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."
Authorities in New York, meanwhile, are deploying counter-terrorism vehicles around landmark sites in Manhattan, including prominent hotels, according to the New York City Police Department.
Nearly 25,000 people, including runners from around the world, competed in Boston's celebrated 26.2-mile race, attracting huge throngs of onlookers, especially near the finish line.
"This is a horrific day in Boston," Massachusetts Gov. Deval Patrick said in a statement. "My thoughts and prayers are with those who have been injured. I have been in touch with the President, Mayor [Thomas] Menino and our public safety leaders. Our focus is on making sure that the area around Copley Square is safe and secured. I am asking everyone to stay away from Copley Square and let the first responders do their jobs."
Explosions Reported at Boston Marathon Finish
BOSTON—Two bombs exploded near the finish line of the Boston Marathon on Monday, killing two people and injuring at least 23 others, Boston police said.
Runners who hadn't finished the race were diverted away from the site and into a family-meeting area nearby, according to an emergency plan that had been in place, the Associated Press reported.
A spokeswoman for Tufts Medical Center in Boston said Monday afternoon the hospital had received nine patients from the blast, and was expecting more. No word was immediately available on their condition.
Explosions Rock Boston Marathon
Charles Krupa/Associated Press
Responders helped an injured man.
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, the AP reported. Another explosion could be heard a few seconds later.
Raw video taken from Copley Square as emergency services responded to two explosions at the Boston Marathon finish line.
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Though much is still unknown about what happened, the Federal Bureau of Investigation is responding to the events, according to officials. Authorities were also trying to determine if there were any suspicious packages in nearby areas, the officials said.
Copley Square Mall closed all its stores and no one could access the Mall at Prudential Center, which is at the finish line.
Robert Rapoport, a radiologist from Delmar, N.Y., running in the marathon, crossed the finish line a minute or two before the explosion. He said he was getting a bottle of water from a volunteer about 50 yards away when the first explosion hit behind him.
"We heard a boom, a loud explosion," he said. He turned to see a column of smoke about the size of a garbage can, rising up as high as five stories.
The cause of the explosion wasn't immediately clear to those at the scene, he said. "It's kind of disorganized around here."
A student at Boston Conservatory heard two loud booms as he was practicing the violin in a practice room at a building at the corner of Boylston and Massachusetts Avenue. He went to the roof and saw people running in all directions from Copley Square. "There was total chaos," he said.
Firetrucks and ambulances flooded the area, as did vehicles with police in helmets.
Runners Phyllis Perkins and Christine Bell, both of Naperville, Ill., were less than a half mile from finish line when they heard the blast. "This was my first [marathon] and at first I thought it was part of the celebration," Ms. Perkins said.
Scenes from the Aftermath of two explosions at the Boston Marathon. Photo: AP.
Then they saw police running. "that's when I knew something was very wrong," Ms. Bell said. "They stopped us and said you are not going any farther," she said. The pair never finished the race.
A White House official said: "The president has been notified of the incident. His administration is in contact with state and local authorities. He directed his administration to provide whatever assistance is necessary in the investigation and response."
At the end of a conference call with gun-control supporters, Vice President Joe Biden talked about the bombings at the Boston Marathon:
"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 are suffering injury. I don't know how many of them are—I'm looking at the television now."
The Boston Marathon is the most elite and prestigious marathon in America. Running it requires that athletes qualify by running an earlier marathon under a certain time. For men 35 and younger, for instance, the qualifying time for Boston is 3:05 or faster, which for most amateurs is lightning fast.
Last year, 21,554 ran Boston, America's oldest marathon dating back to 1897.
Two bombs exploded near the finish of the Boston Marathon on Monday, killing two people, injuring 23 others and sending authorities rushing to aid wounded spectators, race organizers and police said.
One runner, a Rhode Island state trooper, said he saw at least two dozen people with very serious injuries, including missing limbs.
About two 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.
The Boston Marathon said that bombs caused the two explosions and that organizers were working with authorities to determine what happened. The Boston Police Department said two people were killed and 23 others injured.
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. Authorities went onto the course to carry away the injured while stragglers in the 26.2-mile race were rerouted away from the smoking site.
Roupen Bastajian, a 35-year-old state trooper from Greenville, R.I., had just finished the race when they put the heat blanket wrap on him and he heard the first blast.
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"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."
A Boston police officer was wheeled from the course with a leg injury that was bleeding.
"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.
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.
A third explosion was heard about an hour after the first two after authorities warned spectators to expect a loud noise from a water cannon.
"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.