At least three dead as FBI leads 'potential terrorism investigation' in Boston

Three people, including an eight-year-old boy, are now confirmed as dead and more than 100 are injured after two blasts at the finishing line of the Boston Marathon yesterday.

Horrifying images of injured spectators and blood-splattered pavements were caught as television cameras broadcast footage of the explosions.

Participants were also seen lying on the ground as the impact tore through the finish line, sending smoke and debris soaring into the air.

All Irish runners in the marathon are now accounted for, the Department of Foreign Affairs stated.

1/2 #BostonMararthon @IrelandBoston making contact with Irish nationals in area. So far, fortunately, all have been safely accounted for.

— Irish Foreign Ministry (@dfatirl) April 15, 2013

2/2 #BostonMararthon but if you have family that hasn't been in touch & may be in area pl contact us 01-408 2000 and we will follow-up

— Irish Foreign Ministry (@dfatirl) April 15, 2013

The Boston Marathon website states that 50 competitors listed Ireland as their country of residence, with 108 deeming Ireland their country of citizenship.

Last night, Tánaiste and Minister for Foreign Affairs and Trade, Eamon Gilmore expressed his deepest sympathies to the families of those killed and to those who were injured.

"My thoughts are with the people and the authorities in Boston as they continue to deal with this tragic situation", the Tánaiste said.

"I know that there were a significant number of Irish participating or involved in the Marathon, and my Department - in particular the Irish Consulate in Boston - is doing all that it can to make contact with our nationals to check on their situation.

"So far, fortunately, all have been safely accounted for. However, the situation is still developing and I would ask any family who may be concerned for loved ones that they have not heard from and who might have been present in the area to contact my Department at 01-408 2000."

The death toll today rose as the FBI said it was leading a "potential terrorism investigation" by the city's joint terrorism taskforce into the twin explosions.

But reports of a suspect being held at a city hospital were dismissed by Ed Davis, Boston's Police Commissioner, who told a press conference this morning that no suspect had been arrested.

In a televised address, US President Barack Obama said those responsible will feel the "full weight of justice".

Speaking from the White House, he paid tribute to those who helped wounded runners and spectators, saying: "The American people will say a prayer for Boston tonight, and Michelle and I send our deepest thoughts and prayers to the families of the victims in the wake of this senseless loss.

"We don't yet have all the answers but we do know that multiple people have been wounded, some gravely, in explosions at the Boston Marathon."

Mr Obama added: "We still do not know who did this, or why. And people shouldn't jump to conclusions before we have all the facts.

"But, make no mistake, we will get to the bottom of this, and we will find out who did this, we will find out why they did this.

"Any responsible individuals, any responsible groups, will feel the full weight of justice."

The site lists more than 25,000 participants, 347 of whom are British - although it is unclear whether any were caught in the blasts.

The Boston marathon - one of the world's oldest - is held each year on Patriot's Day.

Commissioner Davis said there had been two "simultaneous explosions" near the finish line of the 26.2 mile event around four hours into the race.

He told a press conference in the early hours of this morning that "at least three people" were dead but that exact figures on the number injured would be released later today.

"This cowardly act will not be taken within stride, we will turn every rock over to find the people responsible for this," he said.

Commissioner Davis earlier said there had also been a third explosion at the JFK Library in the city but he did not believe there were any casualties as a result of that blast.

The explosion is not currently being linked with the two at the race.

Bomb disposal teams carried out a controlled explosion on another suspected device, and Commissioner Davis said a number of unattended packages along the marathon route were being treated with caution.

Massachusetts governor Deval Patrick said that Boston would be open today but that it would not be business as usual, with people using the "T" public transport subject to searches.

Max Abrahms, a terrorism expert at Johns Hopkins University in Baltimore, said the explosions could have been the result of foreign or domestic terrorists.

Al Qaida has become decentralised because of years of US action against it, which meant it could be behind small attacks like this, he told Sky News.

But he also said right-wing groups like those led by Timothy McVeigh, who killed 168 in the Oklahoma City Bombing in 1995, could also be behind it because of the 20th anniversary of the end of the Waco siege, in which 76 people died, on April 19.

"This was around the time of year when we might expect to see the Timothy McVeigh-type bomber come out of the woodwork because it is the anniversary of Waco, when the United States invaded a large group of these types of sympathisers," he told the broadcaster.

"I think it is either an Al Qaida-affiliated group or a right-wing extremist group."

The blasts come just six days before the London Marathon on Sunday, prompting a review of security ahead of the event.

Chief Superintendent Julia Pendry, of the Met Police, the event commander for the race, said security arrangements will be reviewed following the explosions in Massachusetts.

She said: "A security plan is in place for the London Marathon. We will be reviewing our security arrangements in partnership with London Marathon."

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

"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."