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BOSTON, April 15 (Reuters) - At least one explosion struck near the finish line of the Boston Marathon on Monday, police and witnesses said.
The explosion occurred as thousands of runners finished the 117th running of the Boston Marathon, with crowds watching and cheering at the finish.
Reporters in the media center heard a blast.
"There was an explosion, police, fire and EMS are on the scene. We have no indication of how many people are injured," a spokeswoman for the Boston Police Department said.
A spokesman for the Boston Marathon told reporters that no one would be allowed in or out of the hotel that was serving as headquarters for the event.
Mike Mitchell of Vancouver, Canada, a runner who had finished the race said he was looking back at the finish line and saw a "massive explosion."
Smoke rose 50 feet (15 metres) in the air, Mitchell said. People began running and screaming after hearing the noise, Mitchell said.
"Everybody freaked out," Mitchell said. (Reporting by Scott Malone and Tim McLaughlin; Editing by Daniel Trotta and Grant McCool)
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