Several times a day, helicopters land and take off from the helipad above Seattle's Fisher Plaza. But this time was different. The sound -- what the lead investigator described as an "unusual noise" -- gave away Tuesday morning that something was amiss. What followed immediately afterward proved it, as a news helicopter tumbled to the ground and burst into flames, with those flames spreading to several parked cars in its path. "I looked and the helicopter was almost immediately pitched sideways and off balance," construction worker Bo Bain told CNN affiliate KING. "And he kind of just nose-dove over the trees, and clipped the top of the trees and crashed just on the other side of the street there."
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Lead NTSB investigator says helicopter made "unusual noise" before crash
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President of helicopter company offers condolences, help to NTSB
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Mayor knew one of the victims, calls the deaths "very personal"
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The incident occurred near the 605-foot Space Needle; one person is in critical condition
The area was already abuzz with commuters heading to work but few tourists, since the @placeholder was still more than two hours from its scheduled opening.