CHARLY TRIBALLEAU/Getty imagesNew York Police Department officers in riot gear entered Columbia University's Hamilton Hall.Dozens of protesters were taken by police into busses in zip ties, The New York Times reported.This is a developing story. Check back for updates.New York Police Department officers in riot gear entered Columbia University's Hamilton Hall, which had been occupied by protesters for roughly 20 hours, according to multiple news reports.According to The New York Times, the NYPD entered the building using a makeshift bridge that allowed them to climb into the second-story window.