Boston blasts: 'Heightened law enforcement'
16 April 2013 Last updated at 03:52 BST
At least three people have been killed and more than 100 injured, some seriously, in two explosions at the finish line of the Boston Marathon
Governor Deval Patrick, speaking at a news conference, confirmed reports that more than 100 people had been injured, some gravely.
He said Boston would be "open" on Tuesday but that there would be "a heightened law enforcement presence".