It was initially believed the parts found in an alley last week were from a Boeing 767's landing gear, but it was subsequently determined they are actually pieces of a wing flap from a jumbo jet of the same model as those that crashed into the World Trade Center, New York Police Department spokesman Paul J. Browne said.
Police kept the area on Park Place in Lower Manhattan roped off as a crime scene, The New York Times reported.
A process of sifting the area for human remains will begin Tuesday, Ellen Borakove, spokeswoman for the city's medical examiner's office, said.
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