Thousands of spectators are expected to flock to Manhattan and Brooklyn to watch fireworks burst through the air from the East River at the Macy’s 4th of July Fireworks show, one of the country’s largest fireworks displays.

The NYPD will be out in full force on July 4th — with violent lone actors and foreign terrorist sympathizers posing significant threats for the Big Apple, police and police sources said.

CBS News New York's Ali Bauman got a preview of how the FDNY and NYPD are preparing to keep the massive crowds safe.