9/11: Increasing security

Passengers are checked at a United Airlines security checkpoint in Terminal One of O'Hare International Airport in Chicago, November 6, 2001. REUTERS/Sue Ogrocki

A U.S. soldier in a military vehicle patrols the financial district as people make their way back to work prior to the New York Stock Exchange reopening September 17, 2001. REUTERS/Dylan Martinez

Members of the civil security unit of the Antibes town coucil wear protective clothing as they take part in a special training exercise against nuclear, biological and chemical weapons attacks in Antibes, southern France, October 19, 2001. ...more

Passengers leave under the watchful eye of a Massachusetts State Trooper (foreground) in the American Airlines terminal at Logan Airport in Boston, Massachusetts September 11, 2001. REUTERS/Brian Snyder

Nero, a bomb sniffing dog with the Miami-Dade police department, goes through newspapers being delivered at the Miami International Airport, September 13, 2001. REUTERS/Colin Braley

A worker of a post office in the town of Lyubertsy outside Moscow, wears protective mask and gloves as she inspects correspondence, October 18, 2001. REUTERS/Dima Korotayev

Transportation Security Administration personal study images from checked luggage on one of 58 new federalized baggage screening machines at the Los Angeles International Airport on December 20, 2002. REUTERS/Adrees Latif

An Italian military police sniper and an American sheriff keep watch at Rome's Ciampino airport before a NATO-Russia Summit on May 27, 2002. REUTERS/Nikola Solic

A video grab taken from security camera footage of a bomb exploding in Atocha railway station in Madrid on March 11, 2004. REUTERS/Handout

A French policeman inspects a carriage, March 18, 2004, in a Lille railways station as security measures were tightened following the Madrid train bombings REUTERS/Pascal Rossignol

A surveillance camera is pictured next to a train at the main railway station in Berlin August 3, 2006. REUTERS/Tobias Schwarz

A policeman stands guard outside an annex of the high court in Madrid, October 31, 2007. REUTERS/Susana Vera

A police officer steps off a bus after making on-board security checks in Paddington in central London, July 11, 2005. REUTERS/Toby Melville

A member of the New York Police Department's Emergency Services Unit patrols at Grand Central Terminal in New York July 7, 2005. REUTERS/Chip East PP05070086

A Belgian bomb disposal expert inspects a suspect suitcase after a remote-controlled robot blew it up on a street near the European Commission headquarters in Brussels March 29, 2004. REUTERS/Thierry Roge

Two Italian Carabinieri check tourists bags at the entrance of the Milan Duomo, July 8, 2005. REUTERS/Daniele La Monaca

Travellers queue at Gatwick international airport on the outskirts of London following the introduction of heightened security measures August 10, 2006. REUTERS/Kieran Doherty

A passenger looks at a flight arrivals screen showing cancellations at Heathrow airport, near London August 13, 2006. REUTERS/Toby Melville

Passengers of easyJet airline talk to the airline's staff as they wait for their flight to Stansted at Son San Joan airport in Palma de Mallorca, Spain August 10, 2006. REUTERS/Dani Cardona

Passengers wait for delayed flights outside terminal one of Heathrow airport in London August 12, 2006. REUTERS/Toby Melville

A Metropolitan Washington Airports Authority employee waits to collect items no longer permitted on planes from departing passengers at the Washington Dulles International Airport in Dulles, Virginia, August 10, 2006. REUTERS/Yuri Gripas

Policemen secure a helicopter landing area as more police was flown in to protect the security fence for the G8 summit in Heiligendamm June 7, 2007. REUTERS/Kai Pfaffenbach

Policemen keep guard from a top of a bus carrying prisoners out of the the Sargodha jail in Punjab province, Pakistan June 24, 2010. REUTERS/Faisal Mahmood

A reporter talks on her phone as smoke is seen coming from Taj Hotel in Mumbai November 27, 2008. REUTERS/Arko Datta

A policeman stands guard at Chhatrapati Shivaji Terminus railway station, also known as Victoria Terminus, in Mumbai December 2, 2008. REUTERS/Arko Datta

A pedestrian (R) walks down the steps while army soldiers wearing protective gears wait for their anti-biochemical terrorism exercise at a subway station in Incheon, west of Seoul, August 19, 2008. REUTERS/Jo Yong-Hak

Police patrol Kuta beach in Bali July 19, 2009 following bomb blasts in Jakarta. REUTERS/Murdani Usman

A bomb technician examines a Nissan Pathfinder sport utility vehicle that was packed with bomb materials in New York's Times Square, May 1, 2010. Police tipped off by a street vendor found and defused a car bomb inside a sport utility vehicle,...more

A New York City police officer uses a metal detector to screen a reveler as he arrives for New Year's Eve celebrations in New York's Times Square, December 31, 2009. REUTERS/Jessica Rinaldi

A security official demonstrates a full body scanner during a photocall at Departure Gate 2 at Hamburg Airport in Hamburg September 27, 2010. Germany started on Monday the voluntary use of two 'L-3 Provision ATD' body scanners for a test period...more

Jeska Stolle tests the three-dimensional (3D) face scanner used to register individual details of passengers at the SAC Siemens airport centre in Fuerth near Nuremberg on March 30, 2007. REUTERS/Michaela Rehle

Bonnie Tse, a San Francisco International Airport customer service agent, has her finger scanned as she shows how the Clear Fast Pass works in San Francisco, California, October 17, 2007. REUTERS/Kimberly White

Washington Metro Transit police officer Eric Croom and his dog Kota inspect the Gallery Place-Chinatown Metro Station in Washington, March 29, 2010. REUTERS/Jason Reed

A Transportation Security Agency (TSA) worker runs the back of her hand between a traveler's breasts during a patdown search at Denver International Airport, the day before the Thanksgiving holiday in Denver November 24, 2010. REUTERS/Rick Wilking more

A Buddhist monk passes by an armed man securing the train station in the troubled Pattani province in southern Thailand February 28, 2011. REUTERS/Damir Sagolj

A TSA agent dons rubber gloves at a security checkpoint at Washington Reagan National Airport in Washington, November 22, 2010. REUTERS/Jason Reed