Boston police say third explosion near JFK library

BOSTON, Massachusetts: Boston police said there was a third explosion Monday near the John F. Kennedy Presidential Library after twin blasts at the city's annual marathon killed at least two people.

"There was a third explosion at the JFK library," Police Chief Ed Davis told a press conference. He said he did not know of anyone being wounded in the third blast, or whether any of the explosions were part of a terrorist attack.