operation, and what they're now putting in some of those packages. >> reporter: headaches, viral videos and an estimated 26 million victims in the u.s. as so-called porch pirates swipe those packages from our doorsteps. tampa police say these two women did just that this week. but one major american town is now doing something about it. >> these are the locations where our gps devices are deployed right now. >> reporter: we're inside the jersey city police burglary unit. they've teamed up with amazon, planting a gps tracking device inside fake packages, and dropping them off on a porch, waiting for a porch pirate to come steal it. >> this morning, the detectives deployed this, and within eight minutes, we had movement on one of the devices. we swooped in and made the arrest, with big smiles on our face. >> reporter: within the first four hours of their undercover sting, police made three arrests. >> the message to the bad guys are, we're going to catch you. >> reporter: and david, the goal here is to catch repeat offenders and deter others, because you simply can't tell which package is rigged. now, jersey city is one of the