A mysterious package left Friday morning in the vicinity of last week's failed bombing in Times Square turned out to be someone's lunch. In the afternoon, an abandoned cooler of water bottles, together with a gift bag from "The Oprah Winfrey Show," caused four blocks of the square to be partly evacuated.

The two incidents occurred within days of Wednesday's abandoned U-Haul truck on the Robert F. Kennedy Triborough Bridge, a last-minute recall of a Dubai-bound Emirates airline flight Thursday and two men arrested Friday after a bomb scare aboard a New York-bound Greyhound bus.

"Once someone reports something that scares people, it starts coming out of everyone's woodwork. It's part of human nature," said Scott Atran, an anthropologist and senior research fellow at John Jay College of Criminal Justice.

Retired FBI executive assistant director Pat D'Amuro, chief executive of Giuliani Security located on Times Square, called the case of nerves understandable.

"Because of the near disaster with the car bomb last week and because of the Pakistani Taliban statement saying the bomber wasn't one of theirs but that they have other people who are going to be coming after us really soon," he said, "there's a heightened concern around the Times Square area about suspicious packages."

Marie-Helen Maras, a security expert and criminal-justice professor at Farmingdale State College, who worked in law enforcement security for the Navy for seven years, said civilians should not be paranoid or panic, but paying attention does save lives.

"If we look back, every attack since 9/11 in the U.S. has been prevented by a vigilant bystander. . . . We are validated to be nervous and I also think it's necessary."

In New York City, there has been a 30 percent increase in reports of suspicious packages since the bomb attempt. Officials said the NYPD usually gets 90 to 100 such calls a day. On Thursday, police received 145 calls.

Police Commissioner Ray Kelly said Friday, "When you have a major event, reports of suspicious packages will go up . . . I think to a certain extent, people are becoming more suspicious, more vigilant and that results in more calls. We understand that's what happens and we are prepared to respond."

With Deborah Morris,

Tom Brune and John Riley

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