(AP/WHAS11) -- Three people were killed in explosions near the finish line of the Boston Marathon.
Martin Richard, an 8-year-old-boy was one of the three people killed in the explosions near the finish line of the Boston Marathon. Krystle Campbell, a 29-year-old restaurant manager, was also killed. Boston University graduate student Lingzi Lu, 23, from China as been identified as the third victim.
A person briefed on the probe says the explosives were made of pressure cookers.
About three hours after the winners crossed the line, there was a loud explosion on the north side of Boylston Street, just before the photo bridge that marks the finish line. Another explosion could be heard a few seconds later.
A law enforcement official says cellphone service was shut down in the Boston area to prevent any potential remote detonations of explosives.
President Barack Obama, responding to the explosions at the Boston Marathon, says the United States does not know "who did this or why" but vowed that whoever is responsible "will feel the full weight of justice."
Police Commissioner Edward Davis says there are no injuries stemming from a third explosion at the JFK Library.
Former Boston Marathon winner Wesley Korir tweeted "I am safe very sad for what happened..God help our people."