Officials within the Usa have launched an investigation following two explosions near the finish line of the Boston Marathon.
FBI investigators launched a “potential terrorist inquiry” as three people were left dead with upward of 100 more injured.
At least 17 individuals are critically wounded with injuries including several amputations.
In a televised address following the incident, president Barack Obama vowed to bring those behind the attack to justice.
“We will discover who did this.
“We will discover why they did this,” he said.
“Any responsible individuals, any responsible groups, will feel the total weight of justice.”
The first explosion came at about 14:50 local time at the north side of Boylston Street.
Seconds later another explosion struck the crows approximately 100 metres further back along the course.
British prime minister David Cameron offered his condolences: “The scenes from Boston are shocking and horrific – my thoughts are with all those that has been affected.”
London Marathon
Meanwhile officials within the UK said security round the London Marathon can be reviewed after the incident in Boston.
However, the development will go ahead, after sports minister Hugh Robertson said he was “absolutely confident” it usually is kept safe.
London had “enormous experience” of delivering major events and the united kingdom had the superior security professionals on this planet, he told the BBC.
He also said he was “horrified” by the Boston blasts.
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