Fighting terrorism in the aisles

Wal-Mart is teaming up with the U.S. Department of Homeland Security to send a message to people across America: "If you see something suspicious in the parking lot or in the store, say something immediately," says Homeland Security Secretary Janet Napolitano in a video promoting the partnership. At least 200 Wal-Mart stores are rolling out security announcements—videos of Napolitano imploring citizens to report suspicious activity—this week. TV screens featuring Napolitano will be stationed at select checkout lanes. By the end of the month, some 588 stores in 27 states will be participating in the program.

MSNBC