Security and terrorism: Jittery backdrops to New Year’s Eve around the world

(CNN) – 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.