An eyewitness captured New York City police officers entering the grounds of Columbia University on Tuesday (April 30) night in an apparent effort to disperse pro-Palestinian protesters who took over a campus building after a nearly two-week standoff with administrators of the Ivy League school.Live television images showed police entering the elite campus in upper Manhattan, which has been the focal point of student protests that have spread to dozens of schools across the U.S. expressing opposition to Israel’s war in Gaza.Columbia University officials earlier on Tuesday threatened academic expulsion of the students who seized Hamilton Hall.A long line of police officers were seen climbing into the building through a second-story window, using a vehicle with a ladder to gain access to the upper floor.The occupation began overnight when protesters broke windows, stormed inside and unfurled a banner reading “Hind’s Hall,” symbolically renaming the building for a 6-year-old Palestinian child killed in Gaza by the Israeli military.