NEW YORK -- Massive 20-ton sanitation trucks, weighted with an extra 15 tons of sand, will surround the iconic New Year's Eve celebration in Times Square, officials said Thursday, describing a security measure meant to stop truck-driving attacks into crowds like those in Germany and France.

The placement of the 65 trucks, along with 100 patrol cars, at intersections surrounding Times Square is a new element to an already heavily policed event that will include 7,000 officers, counterterrorism units and bomb-sniffing dogs.

"We live in a changing world now," New York Police Department commissioner James O'Neil said. "It can't just be, 'What happens in New York? What happens in the United States?' It has to be more, 'What happens worldwide?'"

A Tunisian man who plowed a truck into a Christmas market in Berlin this month killed 12 people and injured 56 others. His attack followed a more deadly assault in Nice, France, in July that left 86 people dead when a man drove a 20-ton refrigerated truck into a crowd celebrating Bastille Day.

Police studied those events in planning their Times Square security.

"As we formulated this year's plan, we paid close attention to world events, and we learned from those events," said Carlos Gomez, the NYPD's chief of patrol.

More than 1 million people are expected to attend the annual ball drop countdown in Manhattan. Officials said they didn't know of any terror threats.