RFID tracker tags for visitors to US

"Planning to visit the US? An electronic tag will keep track of you during your stay there. On an experiment, the US Department of Homeland Security (DHS) is deploying radio frequency identification (RFID) technology to track immigrants entering and exiting the country. The RFID is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. From July 31 the experiment applies to people without green cards entering the US with a visa to work, study or tour. Over the next year, people in these categories will be issued new "I-94" visa cards embedded with an RFID tag at five border crossings of Nogales East and Nogales West in Arizona, Alexandria Bay in New York, and the Pacific Highway and Peace Arch in Washington. The DHS requires that the I-94 cards be carried at all times, says information available in its Web site." Source: thehindubusinessline.com