Security is tight at New Year celebrations in cities around the world, as authorities confront threatened possible terror attacks against public celebrations.
In Sydney, one of the first places marking the dawn of 2016, Australians enjoyed one of their biggest fireworks displays ever — seven tons of pyrotechnics for a 12-minute show that cost $5.1 million.
In Russia, authorities have decided to shut down Moscow's iconic Red Square, a popular spot to ring in the new year. Though not officially acknowledged, the rare move seems aimed at concerns of terrorism following the October downing of a Russian passenger plane over Egypt and Russia's ongoing bombing campaign in Syria.
Also on high alert was Jakarta, Indonesia, where police uncovered plans for a terror attack on the capital during the festivities.
View the photo gallery of New Year's celebrations around the world:
Brussels cancels celebration
In Belgium, the capital's annual New Year's Eve celebration was canceled due to fears of terrorism. Brussels Mayor Yvan Mayeur said crisis analysts determined it would not be possible to adequately screen tens of thousands of people viewing a fireworks show.
Police in Brussels say they have arrested a 10th suspect in connection with the November 13 terror attacks in Paris that killed 130 people. They also reported Thursday that six more people have been detained for questioning about a suspected New Year's Eve terror plot; two people were arrested earlier this week in connection with that suspected plan to attack "emblematic" targets in the capital.
Four of the Islamic extremists who killed 130 people in last month's attacks in Paris were from Belgium.
Belgian soldiers stand guard on Brussels' Grand Place, Dec. 30, 2015, after two people were arrested in Belgium on Sunday and Monday, both suspected of plotting an attack in Brussels on New Year's Eve, federal prosecutors said.
Fireworks cancelled in Paris
Paris has also cancelled its fireworks show and cut back on plans for the evening, such as closing the famed Champs Elysees avenue to cars for only one hour instead of three. Still scheduled is a light show projected on the Arc de Triomphe.
Paris Mayor Anne Hidalgo, in a comment to the French weekly Journal du Dimanche, said that France needs its symbolic passage into the new year to "send a signal to the world" as it continues recovering from the attacks.
In Turkey, authorities detained two suspected Islamic State members Wednesday who were believed to be planning New Year's suicide attacks on crowds celebrating in Ankara, the capital.
New York ready for Time Square celebration
In New York City, thousands of police officers — some armed with rifles and others equipped with radiation detectors and bomb-sniffing dogs — prepared for traditional New Year's celebrations in Times Square, expected to draw more than a million people. Authorities say they are also monitoring overseas communications to detect any threats.
New York Police officers with rifles stand guard in Times Square in the Manhattan borough of New York, Dec. 27, 2015.
Police, the FBI, and federal security officials say there were no specific, credible threats against celebrations in New York or any other U.S. city. But they pledged to be vigilant and proactive following the recent terror attacks in Paris and San Bernardino, California.