NEW YORK (Reuters) - Hundreds of thousands of merrymakers witnessed the descent of the kaleidoscopic New Year’s Eve ball in Times Square at midnight on Sunday, celebrating a century-old New York tradition under an unprecedented umbrella of security.

As many as 2 million people, surrounded by a ring of 40-ton sand trucks and some 7,000 police, gathered in the “Crossroads of the World” to watch the glittering sphere complete its minute-long drop, marking the beginning of 2017.

With the throng counting down the seconds, the crystal-paned ball slid with smooth precision down its pole, mounted on a tower at the head of the plaza. At the stroke of midnight, it touched home, illuminating a giant “2017” sign and sending a shower of fireworks into the sky.

The sights and sounds were experienced by a veritable sea of humanity, sectioned off in block after block of temporary corrals set up to better control the crowd. Millions of others around the world watched the spectacle on television and the internet.

Despite the heavy police presence, or perhaps because of it, thousands of people, many from overseas, arrived early to be dazzled by the flashing signage and entertained by live musical performances by Mariah Carey, Thomas Rhett and Gloria Estefan.

“It’s a very special place, to be in the center of everything tonight,” said Marta Loygorra, 20, who came to Times Square from Madrid, Spain, with her father, Jose Loygorra, 54.

“I’ve always wanted to be here for this and it’s great to be here with my Dad,” she said, cuddling up to him for warmth.

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Jess Smith, 22, of Perth, Australia said that when she booked her New York hotel, she didn’t realize it was just a few blocks north of Times Square.

“It’s crazy. It’s crazy good luck,” she said with a grin.

In the days before the celebration, city and federal officials said they were not aware of any credible threats, and in the event, the party went off without a hitch.

But authorities also said they were taking no chances. A protective perimeter of 65 hulking sanitation trucks filled with sand, as well as about 100 other smaller vehicles, encircled the Times Square area.

Placed in strategic positions, the “blockers” are intended to prevent a repetition of the truck attacks in Berlin and Nice earlier this year, officials said.

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CIRCLE OF TRUCKS

It is not the first time that New York has set up a perimeter of heavy trucks at large gatherings. The same strategy helped protect crowds at the Macy’s Thanksgiving Day Parade in November, after Islamic State militants encouraged followers to target the event, which drew about 3.5 million people.

At times since Donald Trump’s election in November, blocker trucks have been positioned near Trump Tower, his Fifth Avenue headquarters and residence, a short distance from Times Square. The president-elect is spending the holidays in Florida.

For New Year’s Eve, New York also deployed heavily armed police teams, snipers, bomb-sniffing dogs and helicopters. Coast Guard and police vessels patrolled waterways around Manhattan.

John O’Leary, 57, his wife, Claire, 51, and their two children were passing through Times Square on Saturday afternoon during a visit from their native England.

“It’s just amazing,” O’Leary said. “I just can’t believe how they can manage all this, in terms of security.”

U.S. defense and security agencies said they believed the threat of militant attacks inside the United States was low during the New Year’s holiday, though the possibility of an attack, no matter how remote, was always present, they said.

Likewise, New York Police Commissioner James O’Neill said at a briefing this week that there were “no direct concerns” related to this year’s festivities in Times Square.

Even so, he said, “we are going to have one of the most-policed, best-protected events and one of the safest venues in the entire world given all the assets we deploy here.”