Extravagant firework displays lit up the skies from Sydney to New York in a global New Year's party that saw millions set aside their world of worries to welcome 2012.
Turning the page on a year of financial turmoil in Europe and the United States, uprisings across the Arab world, devastation in Japan, and the dramatic killing of Al Qaeda chief Osama bin Laden in his Pakistani hideout, revelers danced to pop stars, drank champagne, and cheered out the final seconds of 2011.
In New York, pop diva Lady Gaga and Mayor Michael Bloomberg hit the switch sending the city's famous crystal ball on its countdown drop. Confetti poured out over Times Square, where up to a million people had been expected, and multi-colored, star-burst fireworks erupted over Manhattan's skyscrapers.
Earlier in Asia, Sydney and Hong Kong set the standard with glittering extravaganzas. The mood was more somber in Tokyo but Dubai led the way in the Middle East and, despite financial crisis, Europe spared no expense on the pyrotechnics.
As the clock moved through the timezones, celebrations in Dubai centered on the Burj Khalifa skyscraper, the world's tallest man-made structure, with a pyrotechnics display even more extravagant than 12 months ago.
London hosts the 2012 Olympics and its firework display kicked off with a recording of the moment the capital learned it would host the Games.
An estimated 250,000 people lined the banks of the River Thames, watching rings of fireworks in the Olympic colors flash in the sky, while the famous clock tower in the parliament building lit up with fireworks at every chime of the Big Ben bell.
Simon Masson, a 47-year-old property developer, spoke for many when he said: "Personally, I'd like good health and happiness for my family, and nationally, I'd like the British economy to pick up a little bit and for things to be a bit better in Great Britain."
There was no avoiding the looming euro-zone crisis in some other European capitals.
In a New Year's address, Italian President Giorgio Napolitano delivered a stark message calling on the nation to make sacrifices to "prevent the financial collapse of Italy".
But in Madrid, many wanted to ignore their country's deep financial woes, gathering in the Puerta del Sol -- the square that became a focal point for the "indignant" protest movement. "Today is a day to forget the crisis," said Luis Zorrilla, a 46-year-old teacher.
In Berlin another spectacular display lit up the night sky with partying at the Brandenburg Gate, while in Paris, some 360,000 people flocked to the Champs-Elysees.
In the heart of Vienna the New Year was rung in by the great bell of Saint Stephen's Cathedral, followed by the strains of the Blue Danube Waltz.
In Amsterdam, revelers watched the first "kiss" between two giant inflatable puppets representing a Dutch boy and girl, which "walked" towards each other as the seconds ticked down to 2012.
Across the Atlantic in Rio de Janeiro, huge crowds of white-clad party-goers -- Brazilians and foreign tourists -- rang in the New Year on Copacabana beach, watching a spectacular "green" fireworks extravaganza.
New York's party was the biggest in the United States, helped by unusually balmy December weather.
A small army of police deployed, including undercover units, anti-terrorism squads and an entire class of newly graduated police academy officers. Backpacks and alcohol were banned and many revelers were forced to wait for hours behind penned-off areas.
"There should be a police officer pretty much within arm's reach," Police Commissioner Raymond Kelly said.
Remote Pacific islands were the first to welcome in the New Year, including Samoa for the first time, having wiped Friday off its calendar by jumping west across the international dateline.
But Sydney really got the party started, its harbor exploding in a blaze of color and light that drew more than 1.5 million people. "Every year we make sure our celebrations are bigger and better than the one before," Sydney Lord Mayor Clover Moore said.
Two hours later the excitement moved to Tokyo, where balloons and fireworks filled the sky, with the Tokyo Tower turning blue.
But the celeration was soon marred by a major 7.0-magnitude earthquake that rocked Tokyo at 2:28 pm (0528 GMT) Sunday.
There were no immediate reports of damage or injury and no tsunami warning was issued.
The quake's epicentre was located near Torishima, an island about 560 (350 miles) south of Tokyo.
The mid-afternoon quake swayed buildings in Tokyo but it did not disrupt the final of the Emperor's Cup football tournament under way at the National Stadium.
In Hong Kong, the city's harbor lit up by a barrage of fireworks fired from several of its iconic buildings, delighting partygoers crammed on to the waterfront and in pleasure boats.
Russia's far eastern regions entered 2012 eight hours ahead of Moscow. Then thousands gathered in the capital's Red Square for another massive firework display that sent rockets 140 meters (400 feet) into the midnight sky.
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