Developing news story (check back for updates):  A pair of explosions rocked an area near the finish line of the Boston Marathon on Monday, leaving at least three people, including one child, dead and more than 130 injured, many critically.

The race was about half-over, with many racers finished, but many still on the route.

In the hours following the blasts, CNN reported two separate explosions near the end of the race at Copley Square. Early video and film footage showed severely injured spectators and plumes of smoke.

As the Boston Globe was reporting late Monday night:

At least three people were killed and at least 140 others were injured this afternoon as two powerful explosions detonated in quick succession near the Boston Marathon finish line in Boston’s Back Bay section, transforming a scene of athletic celebration into bloody chaos.

When the smoke cleared from what officials said may have been a terrorist attack, dozens of victims lay in the street, some unconscious, some grievously injured, including some whose limbs had been torn off by the blast.

The dead included an 8-year-old boy, according to two law enforcement sources briefed on the investigation. Boston Children’s Hospital reported that those treated there included a 9-year-old girl, a 7-year-old boy, a 12-year-old, and a 2-year-old.

At approximately 4:05 pm, the Boston Police Dept. tweeted:

Update 23 injuries2 dead #tweetfromthebeat via @cherylfiandaca

— Boston Police Dept. (@Boston_Police) April 15, 2013

Update: AP is reporting (at 4:26 PM EST) that two unexploded devices have been found in Boston. The Boston Police also announced performance of at least one 'controlled explosion' in the area, but it was not initially clear if that was a confirmed bomb or simply a 'mysterious package.'

Twitter continues to have the most up to date reports. Check back for updates...

Tweets about "explosion marathon"

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This footage was taken by a racer as he/she approached the finish line:

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Footage (via Vine) of one of the explosions:

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Raw footage via WBZ Channel 4 News (Local CBS affiliate):

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This is Fox News' break-in coverage and includes early live footage from the area:

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Footage from the finish line camera:

Boston Marathon Finish Line

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