a mobile device scanning the streets now...
Below, from the company's press release on the "AS&E's Z Backscatter Van™" (their X-ray mobile threat detection unit), emphasis mine:
The system's unique "drive-by" capability allows...X-ray imaging of suspect vehicles and objects while the ZBV drives past....can also be operated in stationary mode*...producing X-ray images of vehiclesScreening can also be accomplished remotely. as they pass by. .. The system is unobtrusive, as it maintains the outward appearance of an ordinary van.
* In Stationary Scan Mode, ZBV operators may elect to scan the occupants of the subject vehicle. For this application, AS&E offers a Personnel Scanning option that may better enable the customer to meet any applicable country-specific regulatory requirements.