TSA rail, subway, bus, truck operations – The Transportation Security Administration's Visible Intermodal Prevention and Response teams (VIPR) conducted 3,895 surface transportation operations in 2010, according to the Department of Homeland Security. Screenings occurred at some of the nation's 500 Amtrak stations.
Screening rail passengers – Amtrak police coordinate with the TSA to spot-check Amtrak's 21 million annual passengers.
Subway baggage searches – Riders make more than 10 billion trips a year on U.S. public transit services, according to the American Public Transportation Association. New York City police sometimes screen passenger bags at subway stops. TSA officers may coordinate with police on these operations.
Spot-checking trucks – About 11 million large trucks drive the nation's highways, according to federal statistics. TSA teams sometimes join local and state law enforcement to patrol the nation's approximately 1,200 trucking weigh stations.
Bus station screenings – TSA teams also join local and state authorities to spot-check the nation's bus stations. In 2009, there were 841,993 buses in the U.S., according to the Bureau of Transportation Statistics.