The London Marathon will be held as scheduled on April 21 despite the explosions in Boston Marathon killed two and injured 23 on Sunday, organizers said.

But security for Sunday's London Marathon will be reviewed, British police said.

London Marathon chief executive Nick Bitel said that there was "absolutely no chance" that this year's marathon would be cancelled.

At least two people were killed and 23 injured after the blasts at the finish line of the event in Boston.

The London Metropolitan Police said a security plan was in place for London's race but "we will be reviewing this".

The BBC quoted he Met Police's Ch Supt Julia Pendry, the commander in charge of policing the London race, as saying: "A security plan is in place for the London Marathon. We will be reviewing our security arrangements in partnership with London Marathon."

British Prime Minister David Cameron said: "The scenes from Boston are shocking and horrific - my thoughts are with all those who have been affected."