Disrupted terrorist plots. Increased police presence. Warnings to stay alert. Fears of terrorism and stepped-up security provide a sobering backdrop to planned New Year's Eve celebrations around the world. In the United States, federal and local security officials are tightening security in high-profile locations, including New York's Times Square and the Rose Bowl festivities near Los Angeles. In Belgium and Turkey, police said they disrupted terrorist plots that would have targeted celebrations to ring in the New Year in the capitals of those countries. Here's a look at the latest news on that front around the world:

UNITED STATES

Before President Barack Obama left for his Hawaii vacation, his top security officials briefed him about a threat, originating from overseas, of possible attacks in New York, Los Angeles and Washington between the Christmas and New Year's holidays, according to senior U.S. officials briefed on the matter. The officials said the threat was uncorroborated and was based on a single source, and it didn't mention specific locations in the cities. But they said they are always concerned about "soft targets" such as large gatherings and mass transit systems. In the wake of attacks in Paris, San Bernardino, California, and elsewhere, the FBI is boosting the number of agents and staff in some of its 24-hour command centers around the country, including in New York, Washington and Los Angeles.

About 6,000 police officers will fan out around Times Square for the annual New Year's Eve celebration there, Police Commissioner Bill Bratton said. "We are not aware of any threat at this time that we deem credible," he said. Among the tools the police will use to guard against would-be criminals or terrorists: cops on helicopters and boats along with hundreds of additional mobile cameras and radiation detectors. It's a grim reminder of the threats posed by terrorist organizations from around the world. In addition, hundreds of officers will carry rifles, said James O'Neill, a top police official in New York. "We are ready," New York Mayor Bill de Blasio said this week. He called New York "the best prepared city in the country to prevent terrorism and to deal with any event should it occur."

New York Police Commissioner Bill Bratton, left, and Mayor Bill de Blasio say the city is ready. They're shown in a photo from a few weeks ago. There will be more cameras watching the route of the Rose Bowl Parade, Pasadena Police Chief Phillip Sanchez told reporters. "It's not the first year we've had cameras, but there will be more of them installed by (the Department of Homeland Security)," Sanchez said. The additional cameras are part of more resources and money being used for the event and the Rose Bowl game, which are considered elevated security events for the first time. The chief of the Los Angeles Sheriff's Department said more officers will be at the parade and later at a celebration at Grand Park. "This is probably largest deployment they've ever had," he said.(Source: CNN)