Force One when the president of the United States is aboard), followed by an F-16 military fighter jet, performed low-altitude fly-overs of New York City and New Jersey. The mission "was set up to create an iconic shot of Air Force One, similar to one that was taken in recent years over the Grand Canyon." While the FAA and select local authorities were given some degree of notification in advance, many other officials and the general public were not. The fly-over of the lower Manhattan financial district created a panic. Many feared it was another terrorist attack like the one that destroyed the twin towers of the World Trade Center on September 11, 2001, or an aborted attack attempt, because of the F-16 following the presidential plane. This led scores of people to leave their desks and large office buildings to be evacuated in a speedy but impromptu fashion. New York City police stated that "federal authorities" told them not to disclose information about the fly-over to the public in advance. President Obama was also not informed beforehand. Like New York City Mayor Michael Bloomberg, President Obama only learned of the incident after the disturbance it caused was already being reported by journalists, bloggers, websites and news outlets. The incident brought intense scrutiny and numerous highly critical comments directed at Caldera. White House officials said President Obama was fuming mad and did not see the need for a new Air Force One publicity photo anyway. Mayor Bloomberg condemned the low flyover and the failure to provide public notice, saying he himself had not been adequately notified, that he was "furious", and that it showed "poor judgment". Senator John McCain stated the flyover photo op was "a fundamentally unsound exercise in military judgment and may have constituted an inappropriate use of Department of Defense resources." The cost of setting up the flyover photo was reportedly $328,835. Observers noted that an expense like this would have been incurred whether or not the photo shoot had been carried out. VC-25 flying time requirements dictate the need for regular training flights. Had the flyover not been ordered, a similar expense would have been incurred in the normal course of VC-25 flight training. Caldera, after meeting with White House officials, issued a public apology for the incident, stating, "Last week, I approved a mission over New York. I take responsibility for that decision. While federal