The explosions hours into the 117th running of the iconic 26.2-mile race came well after the elite runners had finished, but near the time when the bulk of the about 27,000 runners were laboring toward the finish line.
Two bombs hundreds of yards apart went off within seconds of each other on what was also Patriots Day. Dazed and bloodied victims walked around seeking help as officials rushed to their aid, taking them to one of the medical tents that dot any marathon route. Some victims had severed limbs.
There was no immediate claim of responsibility and officials said there had been no warning to what officials were considering an act of terrorism.
“Any event with multiple explosive devices — as this appears to be — is clearly an act of terror, and will be approached as an act of terror,” one federal official said. “However, we don’t yet know who carried out this attack, and a thorough investigation will have to determine whether it was planned and carried out by a terrorist group, foreign or domestic.”
President Obama pledged federal help for the investigation and cautioned people not to jump to conclusions. But he also struck a firm note.
“But make no mistake, we will get to the bottom of this. And we will find out who did this; we’ll find out why they did this. Any responsible individuals, any responsible groups, will feel the full weight of justice,” he said from the White House hours after the tragedy.
“We’re still in the investigation stage at this point,” Obama said. “But I just want to reiterate we will find out who did this and we will hold them accountable.”
Boston officials told reporters at a nationally televised briefing that there were no suspects, but they acknowledged they were questioning some people.
A federal law enforcement official said authorities were questioning a Saudi national who was taken to a Boston hospital with injuries. The official also said authorities are “desperately seeking” a Penske rental truck seen leaving the race site.
Another federal official said that they believe the explosive devices were small bombs placed in small receptacles and that at least one was detonated in a trash can. Another federal official said the bombs appear to have been “unsophisticated” and did not include plastic explosives.
Patriots Day commemorates the first battles of the American Revolution. One of the highlights is the marathon, which attracts runners from around the world. This year, about 27,000 runners were eligible to compete.
The elite runners finished in 2 1/2 to 3 hours. More than five hours into the race, as the main body of athletes moved toward the finish line, at least two explosions shattered the celebratory mood. Both were along Boylston Street.
The explosions were “nearly back to back” along the viewing area, witnesses said. Two more devices were “quickly found and dismantled” nearby, an ATF official said.
Another object was found inside a “military style” duffel bag, but it was unclear if it was connected to the main explosions, the ATF official said. A sixth “event” took place near the JFK Library, but that was later discounted as an unrelated fire.
The area of the blasts was a major trauma scene as ambulances rushed by and officials tried to move people to hospitals.
Officials said at least three people had died. The Associated Press reported that at least 134 injured were hospitalized, with 15 in critical condition.
Runners and spectators described a chaotic scene when the explosions went off, with people fleeing in panic.
“I just turned around and saw the smoke, and I just started sprinting,” said a 19-year-old woman from New York City named Francesca, who declined to give her last name.
Her sister, Mica, who also declined to give her last name, was watching from about a block away. “It sounded definitely like a bomb,” she said.
Updated 9:30 PM Tuesday
Sources close to the investigating have stated that the explosions were carried out by pressure cookers and hidden in duffel bags packed with nails and ball bearings,
The FBI has said it will go to the “ends of the Earth” to find those who used pressure cooker bombs to kill three and injure more than 170 people at the finish line of the Boston Marathon.It has also become apparent that law enforcement now have some of the bomb components in their possession and investigating further ,but they are currently unaware what exactly set off the bomb explosiveThe second of the three victims killed in the attack has been named as 29-year-old restaurant manager Krystle Campbell, of Medford, who had been in Boston to take a picture of her boyfriend crossing the finish line.Her father, William Campbell, says his daughter was “very caring, very loving person, and was daddy’s little girl.” He says the loss has devastated the family.President Barack Obama, who has announced he will visit the city on Thursday, labelled the twin-bombing an “act of terror”.Speaking at a news conference, he said: “What we don’t yet know, however, is who carried out this attack or why, whether it was planned and executed by a terrorist organisation, foreign or domestic, or was the act of a malevolent individual.”He added: “What I have indicated to you is what we now know. We know it was bombs that were set off. We know that obviously they did some severe damage. We do not know who did them.”We don’t have a sense of motive yet. So everything else at this point is speculation.”The FBI said it was following a number of leads in the wake of the attacks but special agent Richard DesLauriers declined to say whether anyone was in custody.Mr DesLauriers said: “We will go to the ends of the Earth to identify the subject or subjects who are responsible for this despicable crime, and we will do everything we can to bring them to justice.”Doctors have revealed the extent of the injuries suffered by those caught in the blasts, including details of a nine-year-old girl who had lost her leg and a 10-year-old boy who suffered deep shrapnel wounds.
Several people have had to have limbs amputated and others are at risk of losing legs following the blasts that ripped through crowds during the city’s marathon.
Doctors at Massachusetts General Hospital, one of several hospitals where victims were taken, told reporters eight people were in a “severe” condition.
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.”
A total of 17 people remain in a critical condition
The first victim killed in the blasts in the heart of the city to be named was eight-year-old Martin Richard, who lived in Boston.
Martin had been waiting with his brother, sister and mother at the finish line for his father, who was running the race.
The bombs went off within seconds of each other and about 100m (330ft) apart on the same street, blowing out windows and sending smoke and debris into the air.
The explosions happened four hours into the race and about two hours after the men’s winner had crossed the line, as amateur runners were reaching the finish.
More than 17,000 competitors had completed the race by the time the blasts struck.
Police commissioner Ed Davis said the area around the blast areas is the most complex crime scene in history of the department.
Authorities are now looking for amateur video and photographs that can give clues to who set off the bombs.
Security has been stepped up in Washington and New York, and Boston itself is a city on high alert, with armoured vehicles seen on the streets on Tuesday and random checks of backpacks on public transport.
Earlier, a plane was grounded at the city’s Logan Airport over security concerns.
There have been no immediate claims of responsibility for the attack, the most serious in the US since the 9/11 World Trade Centre atrocity. Al Qaeda-linked groups and militant white extremists have attacked targets in America in the past.
The Pakistani Taliban, who have previously threatened attacks in the US, have denied any involvement.
Police are said to have questioned a 20-year-old Saudi Arabian man who is being treated for injuries at a hospital in Boston. Officers have searched his apartment in Revere, according to his flatmate.
More than 25,000 people were registered as taking part in the race, 374 of whom were British. There were also 108 Irish athletes.
The British Foreign Office has said it is not aware of any British nationals who have been injured but that it will continue to monitor the situation.
FBI identified the two bombers as being Tamerlan Tsarnaev and his brother Dzhokhar Tsarnaev. Tamerlan was killed that day in a gunfire exchange with the police and Dzhokhar is being charged for the bombings, being caught on CCTV’s during the incidents.