Boston blasts: 'I heard explosion after finishing marathon'
15 April 2013 Last updated at 22:36 BST
British runner Stuart Singer has said that the point where the bombs exploded at the end of the Boston marathon was by the family 'meet-and-greet' area.
Mr Singer said he heard the explosion after completing the marathon but was only aware it was a bomb after seeing news coverage.
The incident reportedly came about two hours after the winners crossed the line.
The cause of the explosions has yet to be confirmed.