A Boston hospital said at least 15 police officers were wounded during last night's pursuit of terror suspects, local radio station WBUR reported.
The officers has mainly suffered "abrasions, bruises, strains, sprains and fall injuries" and most had been discharged, the station quoted St. Elizabeth's Hospital spokesman Chris Murphy as saying.
Among those terribly injured by the Boston marathon bombs was a dance instructor. Adrianne Haslet-Davis lost her foot in the explosion.
The mother of the two brothers suspected of carrying out the Boston bombings told ITV News they saw last year's race but are innocent.
Boston's marathon bombing suspect Dzohkhar Tsarnaev was charged with an offence that could lead to the death penalty, if he is found guilty.