9:00 P.M. Boston police state during press conference that at least 3 people killed in marathon bombing
8:15 P.M. The Boston Globe reports that the fire at JFK Library is likely not tied to the marathon explosions. Tom Putnam, director of the library said the problem there appeared to be a mechanical fire that had nothing to do with the Back Bay bombings. As a precaution, police bomb squads performed a sweep of the Dorchester complex, he said.
8:00 P.M. Law enforcement bulletin puts latest numbers at least 115 injured from explosions
7:30 P.M. The Navy has sent one of its bomb-disposal units to Boston to assist local authorities as needed in the aftermath of the two explosions near the Boston Marathon’s finish line.
6:45 P.M. NBC News Pete Williams reports that one of the victims was an eight-year-old boy. WCVB-TV Boston reports that the Boston Children’s Hospital is caring for seven patients, putting the total toll injured at an estimated 105 people.
6:30 P.M. President Obama said (http://fxn.ws/12g5ZCe) that officials do not know who is behind the attack on the Boston Marathon, but vowed that those responsible will “feel the full weight of justice.”
6:00 P.M. The Boston Police Commissioner told reporters that in addition to two explosions near the finish line of the Boston Marathon, a third explosion occurred at the city’s JFK Library, but that it’s not clear if it was connected to the other detonations. CBS News (http://cbsn.ws/YYc) 5qgis reporting that library sources say the incident there may have been a mechanical fire.
Police Commissioner Ed Davis said that there were “multiple casualties” at the site of each of two bomb blasts along the marathon route.
4:50 P.M. Explosions occurred 50-100 yards apart. All victims removed from the scene. Third incident reported at JFK Library a half an hour ago; third event believed to be related to initial explosions. Boston Police Commissioner Davis says latter situation is unfolding.
4:37 P.M.: Tentative reports of two additional devices found at the scene.
4:23 P.M.: Police official tells ABC News reporter that these were indeed bombings. Police assume they were set off by portable explosive devices.
4:05 P.M.: Initial reports from Boston police indicate two dead and 22 injured, according to ABC News. Officials are testing the air at the scene.
3:56 P.M.: Reports of a police-controlled explosion near the scene of the initial blasts.
3:42 P.M.: ABC News reports severe injuries and casualties from the explosions, including children suffering severe burns and people with lost limbs.
Although there is no word yet whether this is a terrorist attack, reporters note that this area is where spectators and family members often gathered to celebrate with runners at the end of the race–the location as well as the timing of the explosions would seem as if they were optimized to do the maximum amount of damage.
3:35 P.M.: A report on The Washington Post indicated that the second explosion occurred about 15 seconds after the first. The area has been evacuated and the race halted.
The blasts occurred at approximately 2:50 p.m. at the intersection of Boylston and Exeter Streets in Boston, Massachusetts. Firefighters and other first responders were quickly on scene.
CORRECTION: This post initially attributed the news to the Wall Street Journal.
3:23 P.M.: There have been reports of two powerful explosions at the finish line of the Boston Marathon, as well as reports of multiple injuries. Stay tuned for more updates.