TSAThat feeling of being watched? It might not be all in your head – especially if you’re waiting to board an aircraft. In an effort to identify potentially dangerous persons, the Department of Homeland Security’s Transportation Security Administration (TSA) is stationing specially-trained behavior-detection officers at 161 airports across the U.S. The officers, who could be posted anywhere, don’t focus on race, ethnicity, nationality, or gender, but attempt to identify those travelers who show an unusual level of stress or nervous behavior. Suspicious passengers could be subjected to a secondary security screening, or referred to police (detection officers don’t have arrest powers). In 2008, officers required nearly 99,000 passengers nationwide to undergo secondary screenings. Nearly 9,900 were questioned by police; 813 were arrested. Each week, officials perform additional screenings on dozens of passengers in Miami and Fort Lauderdale. In March 2008, officers spotted a traveler about to board a Fort Lauderdale-to-Charlotte flight. A secondary screening uncovered 209 grams of the narcotic Ecstasy, with a street value of $2.5 million. In February 2008, officers at Miami International Airport detected a traveler with suspicious documents who was acting strangely. The man ran after he was flagged for additional screening. Police and TSA officers chased him, following him as he ran from the terminal and jumped off a second-story ledge onto the sidewalk, breaking an arm. He was arrested for resisting arrest, disorderly conduc,t and possessing several identification documents. It isn’t easy to pick a detection officer out in a crowd. They work in teams of two and wear TSA uniforms, blending in with the regular screeners at security checkpoints. Detection officers are selected based upon their intelligence, maturity and ability to work with others. Officers undergo behavior training, including how to spot suicide terrorists. Officials have set up specific guidelines to determine what is considered normal behavior “in an airport environment;” officers respond only if a passenger strays from the criteria. Observing passengers doesn’t end at the airport. On an unspecified number of international and domestic flights, federal air marshals pick up the trail, blending in on flights with passengers and covertly looking for suspicious behaviors. Agents in the Federal Air Marshal Service are authorized to arrest and to use lethal force. In December 2005, air marshals shot and killed Rigoberto Alpizar of Maitland, Florida, after he boarded an Orlando-bound American Airlines flight from Miami. Alpizar, 44, had said there was a bomb in his backpack; he later made a threatening move, which prompted marshals to open fire. Alpizar didn’t have a bomb; his wife claimed he had bipolar disorder.