BOSTON — Update: Boston police say there's been a third explosion in the city, following two blasts near the finish line of the Boston Marathon that killed two people and injured many others.
Police Commissioner Edward Davis says authorities aren't certain that the explosion at the JFK Library was related to the other blasts, but they're treating them as if they are.
David says there are no injuries stemming from the third explosion.
He urged people to stay indoors and not congregate in large groups.
In a press conference this afternoon, officials gave out two phone numbers: Family members looking for runners can call 617-635-4500; anyone who may have witnessed anything that would help with the investigation should call 800-494-TIPS.
Gov. Deval Patrick said President Barack Obama has assured him full cooperation from the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives as the investigation continues.
Officials are asking people to stay out of crowds and make their way home.
Eagle-Tribune reporter Jill Harmacinski heard two explosions. There are reports of deaths and people who have had their limbs blown off. The explosion was just before the photo bridge near the finish line and Lenox Hotel and was apparently outside of a building. The explosions were felt blocks away.
Bloody spectators were being carried to the medical tent that had been set up to care for fatigued runners. Police wove through competitors as they ran back toward the course.
"There are a lot of people down," said one man, whose bib No. 17528 identified him as Frank Deruyter of North Carolina. He was not injured, but marathon workers were carrying one woman, who did not appear to be a runner, to the medical area as blood gushed from her leg. A Boston police officer was wheeled from the course with a leg injury that was bleeding.