Confetti flies over New York's Times Square after the clock strikes midnight during the New Year's Eve celebration. The Associated Press

New Year's fireworks explode over the River Thames and the Palace of Westminster's Elizabeth Tower, known as Big Ben.

People celebrate the New Year in Karachi, Pakistan, on Friday.

From left, Lucy Cooke, Katie Cooke, Amy Middlemiss and Clarissa Newham use torches to display the year 2016 as they get ready to celebrate the new year in Edinburgh, Scotland, on Thursday.

Participants take to the street during the Winter Carnival in Newcastle, England, to celebrate the passing of the old year and to welcome the New Year, on Thursday. The Associated Press

A woman photographs her friend in front of the Great Pyramids illuminated for New Year's Eve in Giza, near Cairo, Egypt, late Thursday.

The moon is visible at midnight on New Year's Eve at the Giza Pyramids near Cairo.

Police officers block an entrance to Red Square for security reasons on New Year's Eve in Moscow, Russia, on Thursday. St. Basil's Cathedral looms at right, and the Kremlin wall is at left.

Fireworks light the sky above the Brandenburg Gate shortly after midnight in Berlin. Hundreds of thousands of people gathered for the celebrations in the area around the Brandenburg Gate.

Fireworks light the sky above Cathedral Square in Vilnius, Lithuania, shortly after midnight.

Fireworks explode over the temple of the Parthenon at the Acropolis during the New Year celebrations in Athens.

Revelers photograph a five-minute video performance displayed on the Arc de Triomphe as part of New Year's Eve celebrations in Paris.

People celebrate the New Year with champagne in the historic center in Brussels. The New Year's Eve fireworks display and all official events were canceled in Belgium's capital because of threats of a terrorist attack.

Pedestrians wait to be searched as they enter Times Square in New York on Thursday. About 1 million people are expected to attend festivities on Times Square, along with nearly 6,000 New York City police officers, including members of a specialized counterterrorism unit.

New York police officers patrol behind barricades in Times Square in the hours leading up to the New Year's Eve celebration. Nearly 6,000 armed police officers were guarding Times Square.

Hundreds of thousands celebrate the arrival of 2016 in Times Square in New York. The Associated Press