In a statement, Sharif El-Gamal, the president of Soho Properties, which owns 51 Park Place, said workers called the city and the police as soon as they discovered the landing gear. He said the company is cooperating with the city and the police to make sure the piece of equipment "is removed with care as quickly and effectively as possible."
The medical examiner's office will complete a health and safety evaluation to determine whether to sift the soil around the buildings for possible human remains, police said.
Patricia Riley, whose sister Lorraine Riley was killed in the Sept. 11 attacks, said the landing gear discovery was "very strange."
"Twelve years later we are still finding remnants of the attack on our country," she said. "... For years to come we'll continue to find things that we didn't see before. Hopefully they'll serve as a reminder that we have to stay vigilant."
Outside the Islamic center building, known as Park51, a police officer stood next to the door on Friday and a police barricade was set up to contain the many journalists who had gathered to try to see the piece of the plane.
The landing gear could not be seen from the sidewalk so commuters rushed by and looked quizzically at the gathering.
The Park51 space, a former Burlington Coat factory, is a five-story, mildly rundown building. The piece of plane is wedged in an alley space between that building and 50 Murray St., which is a luxury loft rental building.