The blasts took place in a crowd of spectators, just feet away from the finish line on Boylston Street where hundreds of runners were completing the world's oldest annual marathon, whose history dates back to 1897. 

Witnesses claimed they had seen victims who had lost limbs.

An eight-year-old boy was among the dead.

At the city's Children's hospital a nine-year-old girl, a seven-year-old boy, a 12-year-old and another child aged two were among the injured, according to the Boston Globe.

It was reported that the explosion had happened in the Fairmont Copley Plaza which is on St. James just a few blocks from the finish line.

The Fairmont updated its Twitter feed with the following message: "Explosions reported on Boylston Street. Only hotel guests and colleagues allowed into the building at this time."


There was later reports of a third bomb at the JFK Library in Boston, although it later turned out this had been a fire unrelated to the finish line explosion five miles away.

A further two unexploded bombs were also found near the end of the 26.2 mile (42km) course as part of what appeared to be a well coordinated attack but they were safely disarmed.

The two devices that caused the carnage had detonated without warning at about 2.50pm local time, the Boston Police Commissioner Ed Davis said.

The devices reportedly used gunpowder as the explosive and were packed with ball bearings and other shrapnel to maximise injuries.

Dozens of injured people were taken to local hospitals where some remained in a critical condition.

No-one has yet claimed responsibility for the attack.

United States President Barcak Obama, at a briefing at the White House, said: "The American people will say a prayer for Boston tonight.

"Michelle and I send our deepest thoughts and prayers to the families of the victims in the wake of this senseless loss."

Obama said he had spoken with the FBI director and the Department of Homeland Security, who were coordinating the federal response.

"We will find out who did this and we will hold them accountable," he said.

"Make no mistake, we will find out who did this and why they did this, and the groups or individuals responsible will feel the full weight of justice."

The Massachusetts Governor, Deval Patrick, said the city would be open tomorrow "but it will not be business as usual".

The incident came about three hours after the winners, Ethopia's Lelisa Desisa and Kenya's Rita Jeptoo, crossed the line of the race which is traditionally held on Patriot's Day, a civic holiday in Massachusetts commemorating the anniversary of the Battles of Lexington and Concord, the first battles of the American Revolutionary War.

Nearly 25,000 runners were taking part in the event, which was being held for the 117th occasion.


Officials from the Virgin London Marathon, which is due to take place next Sunday (April 21) immediately expressed their sympathies.

"We are deeply saddened and shocked by the news from Boston," said Nick Bitel, the chief executive of the London Marathon.

"Our immediate thoughts are with the people there and their families.

"It is a very sad day for athletics and for our friends and colleagues in marathon running.

"Our security plan is developed jointly with the Metropolitan Police and we were in contact with them as soon as we heard the news."

Metrpolitan Police Chief Superintendent Julia Pendry said: "A security plan is in place for the London Marathon.

"We will be reviewing our security arrangements in partnership with London Marathon."

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