Finally, with the cooperation of the technical staff, the FBI spent quite some time cross-referencing the store's inventory of phones and matching the serial numbers of unregistered phones sold recently. Next, it was up to the technical personnel to investigate, and it wasn't until evening that they were able to pinpoint Frank's unregistered phone number.
While the technical staff handled this part of the investigation, Morrison and his team were not idle. By matching vehicles, they successfully located the mini warehouse, but with so many warehouses, the staff couldn't determine which one Frank was using. So, Morrison divided the personnel, with one part continuing to investigate vehicle information, and two people stayed to verify information on the comings and goings of personnel and the warehouse details with the staff.
