NEW YORK The New York Police Department is assigning thousands of extra patrols in Times Square on New Year's Eve, but they won't all be in plain sight.
There will be uniformed officers, bomb-sniffing dogs and heavily armed counterterrorism teams. But there also will be plainclothes officers, assigned to blend into the crowd.
Many officers will be wearing palm-size radiation detectors designed to give off a signal if they detect evidence of a dirty bomb, an explosive intended to spread panic by creating a radioactive cloud.
Police Commissioner Raymond Kelly says Times Square will be the safest place in the world on Dec. 31.
Hundreds of thousands of people are expected to pack into Midtown Manhattan on Monday night to see the famous crystal ball drop and ring in 2013.
The ball got its final test run Sunday on the 130-foot pole atop One Times Square, reports CBS New York station WCBS-TV.
The ball is comprised of nearly 2,700 Waterford crystals and 32, 256 LED lights and weighs 12,000 pounds - nearly six tons.
Ed Crawford, chief executive officer of Philips Lighting company, told the station the ball is the perfect device to test cutting edge technology. "We've used the Times Square ball, really, as a laboratory to push the boundaries of what lighting can do in your home," Crawford said.
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