SPRINGFIELD, Ill. (AP) – Law enforcement departments’ powerful devices that mimic cell towers and track phone locations are raising privacy concerns and inspiring legislation to restrict their use in criminal investigations.

Illinois is among states around the country trying to set rules for the suitcase-sized cell-site simulators, also known as Stingrays. They are capable of capturing data for hundreds or thousands of cellphones in a particular neighborhood – not just the cellphone police are after.

Pending legislation would require warrants to use the device and data from individuals not subject to an investigation must be deleted within three days. The measure passed the Illinois Senate with near unanimous support and cleared its first House committee last week.

Twelve states have passed laws addressing the technology. Connecticut lawmakers last week sent the governor legislation that restricts the devices’ use.