Transcript for NYPD focuses to keep America's largest New Year's Eve party safe
Now to major cities on high alert from coast to coast, as the country counts down to the new year. Unprecedented security surrounding New York's Times square. They call it the ring of steel. More than 1 million people expected. Many have already been there for hours. Heavily-armed police, snipers, and specially-trained dogs on the scene. The show of force follows the deadly terror attack here on Halloween, and the shooting massacre in Las Vegas. Marcus Moore is there in times square. Reporter: With just hours to go keeping America's largest new year's eve party safe the focus tonight of an unprecedented security effort. Searches at hotel entrances. Vapor wake dogs sniffing for any scent of an explosive. And revelers bundled-up and shoulder to shoulder, forced into multiple checkpoints throughout the secure perimeter. We're seeing police everywhere. Reporter: We're hours from the ball drop, and already there's a long lines of people waiting to get into times square, many lines leading right to those checkpoints. Trying to reduce the risk of explosives and weapons getting past the 22-block perimeter, authorities banning large bags and backpacks. We didn't know you couldn't bring backpacks in. Reporter: We meet New York City's counter terrorism chief James waters amidst the operation. We're well prepared. This is the safest place in the world. Reporter: Fresh on his mind, the subway bombing earlier this month. October's deadly truck attack on a New York jogging path. And that Las Vegas rampage that killed 58 people, the gunmen firing from the 32nd floor of the mandalay bay hotel. Police in New York have a plan in place for just that scenario. Snipers in the buildings, and officers in the air, their eyes trained on the crowd and the buildings surrounding them. And Marcus joins us live from inside times square. We see the barricades and crowds just behind you. They've been on lockdow for hours now? Reporter: Tom, that's right. Some of the people behind me have been here since 9:00 A.M. This morning. You can see they're grouped in sections, and there are police officers ground level, keeping a very close eye tonight. Tom? Marcus, thank you. Next tonight, the life-threatening cold gripping much of the country.
This transcript has been automatically generated and may not be 100% accurate.