The Homeland Security department took its "If You See Something, Say Something" campaign into more than 800 Walmart stores across the United States at the height of the 2010 holiday shopping season.
The anti-terrorism agency began playing a short video message at checkout stations to remind shoppers to be extra vigilant and to call the police if they witness any suspicious activity.
'If You See Something, Say Something' Video
"Hi, I'm Janet Napolitano, Secretary of the Department of Homeland Security," the video begins. "Homeland security begins with hometown security. That's why I'm pleased that Wal-mart is helping to make our communities more safe and secure.
"If you see something suspicious in the parking lot or in the store say something immediately," Napolitano says in the video.
"Report suspicious activity to your local police or sheriff. If you need help, ask a Walmart manager for assistance. Thank you for doing your part to help keep our hometowns safe."
History of 'If You See Something, Say Something'
The "If You See Something, Say Something" has been effective in engaging the public and key frontline employees in identifying and reporting "indicators of terrorism, crime and other threats," Homeland Security officials say.
The "If You See Something, Say Something" campaign was originally put in place by the New York City Metropolitan Transportation Authority in 2002, but adopted by the Department of Homeland Security.
The Homeland Security department's "If You See Something, Say Something" partners also include the Mall of America, the American Hotel & Lodging Association, Amtrak, the Washington Metropolitan Area Transit Authority, and sports and general aviation industries.