Participating stores , eventually including 588 from 27 states , will play a short video message at select checkout locations to remind shoppers to contact local law enforcement to report suspicious activity , said a DHS statement . DHS expands ` `` If You See Something , Say Something '' campaign . `` Homeland security starts with hometown security , '' said DHS chief Janet Napolitano . 588 Walmarts stores joined Monday , Metropolitan Transportation Authority said statement . Program started by New York City 's Metropolitan Transportation Authority .
DHS expands ` `` If You See Something , Say Something '' campaign . `` Homeland security starts with hometown security , '' said DHS chief Janet Napolitano . 588 Walmarts stores joined Monday , Metropolitan Transportation Authority said statement . Program started by New York City 's Metropolitan Transportation Authority .