Police plan tight security at Times Square
Since then, the NYPD has maintained a higher profile in Times Square, with mounted police and foot patrols outside hotels, restaurants and Broadway theaters.
The department even elevated its neon "New York Police Dept." sign on West 43rd Street several feet so it's more visible.
The usual security is bolstered each New Year's Eve by an army of extra patrol officers who use police barriers to prevent overcrowding and for checkpoints to inspect vehicles, enforce a ban on alcohol and check handbags.
Revelers will see bomb-sniffing dogs, heavily armed counter-terrorism teams and NYPD helicopters overhead.
What won't be as evident are the plainclothes officers assigned to blend into the crowd and other officers keeping watch from rooftops.
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.
The bomb squad and another unit specializing in chemical and biological threats will sweep hotels, theaters, construction sites and parking garages.
They will also patrol the sprawling Times Square subway station.
The NYPD also will rely on a new network of about 3,000 closed-circuit security cameras carpeting the roughly 1.7 square miles south of Canal Street, the subway system and parts of midtown Manhattan.
In recent years, police stationed at high-tech command centers in lower Manhattan began monitoring live feeds of Times Square, the World Trade Center and other sites.
Times Square isn't the only show in town this New Year's Eve - or the only security concern. Police also will be beef up patrols in Central Park, site of a midnight run, and at fireworks displays at the Statue of Liberty.
The NYPD harbor unit will keep an eye on 33 dinner cruises on the city's waterways. Add to the list the Phish concert at Madison Square Garden.
On a smaller scale in outlying neighborhoods, police are concerned about a phenomenon seen in past years: people who ring in the new year by firing guns into the air.
"We urge people not to do that," Kelly said.
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