The Department of Homeland Security (DHS) has enlisted retailing giant Wal-Mart to join forces for the safety and security of the nation campaign.

According to DHS Secretary Janet Napolitano, the discount retailer is joining hands with DHS to promote its If You See Something, Say Something campaign which was started to make U.S. citizens play a vital role in homeland security by encouraging them to be vigilant.

Homeland security starts with hometown security, and each of us plays a critical role in keeping our country and communities safe, said Secretary Napolitano. I applaud Walmart for joining the 'If You See Something, Say Something' campaign. This partnership will help millions of shoppers across the nation identify and report indicators of terrorism, crime and other threats to law enforcement authorities.

The campaign was primarily started by New York City's Metropolitan Transportation Authority and received $13 million in funding from DHS Transit Security Program.

DHS also joined hands with General Services Administration (GSA) and Federal Protective Service (FPS) to expand the public awareness campaign to 9,000 federal buildings in U.S. Other partners in its fight for homeland security include Mall of America, the American Hotel & Lodging, Amtrak, the sports and general aviation industries and state and local fusion centers across the country.

Around 230 Wal-Mart stores launched the campaign on Monday while a total of 588 stores are due to join the campaign in the coming weeks. The program includes projecting a video message at stores that encourage shoppers to contact law enforcement agencies if they sight any suspicious activity.

The video is timed to reach out to holiday shoppers when hordes of customers will be thronging the Wal-Mart aisles.

Wal-Mart spokesman Dan Fogleman told MSNBC: Wal-Mart is a place where people gather, it's a place where you sometimes see your neighbor the most. It is important to Wal-Mart that it help protect the safety of its community.