NEW YORK:New Yorkpolice said Friday that they have found a fragment of one of two airplanes that slammed into theWorldTradeCenteronSeptember 11, 2001. The huge chunk of aircraft was found wedged between two office buildings in lowerManhattan.

Police said the plane fragment appeared to be "part of a landing gear, apparently from one of the commercial airliners destroyed onSeptember 11, 2001."  Authorities said it will not be removed until the area has been thoroughly examined, including for possible human remains.

"The NYPD is securing the location as it would a crime scene, documenting it photographically and restricting access until the Office of the Chief Medical Examiner completes its health and safety evaluation protocol, after which a decision will be made concerning sifting the soil for possible human remains," a police statement said.

The aircraft was one of two commandeered 12 years ago by Al-Qaeda extremists and flown into theTwinTowers, destroying two of the nation's most iconic buildings.

Authorities were alerted to the chunk of wreckage on Wednesday after surveyors hired by an owner of one of the two buildings found what they believed was damaged machinery.