(AP) — Law enforcement departments' powerful devices that mimic cell towers and track phone locations are raising privacy concerns and inspiring legislation to restrict how police can use the technology 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, which have the capability to capture data for hundreds or thousands of cellphones in a particular neighborhood — not just the cellphone police are after.

"It's a pretty unusual technology because it's highly powerful but not very targeted," said Sen. Daniel Biss, a suburban Chicago Democrat sponsoring legislation to require that law enforcement get search warrants before using the device. The bill cleared the Senate last month with unanimous support and it passed its first House committee Tuesday.

The bill also would require police to delete data from people who are not subject to an investigation within three days and prohibit them from using data to investigate individuals who were not included in a search warrant.

The Chicago Police Department, which is being sued to release records about how it uses this technology, did not take a position on the bill. The Illinois State Police is neutral. Last year, the federal Justice Department set guidelines for its agencies on how to use Stingrays, including requiring search warrants except in emergencies and deleting data every month.

"We're just looking to say Illinois law enforcement agencies must comply with the same basic constitutional protections that the federal government needs to comply with when utilizing this powerful technology, which has the ability to monitor citizens en masse," said Rep. Ann Williams, a Chicago Democrat sponsoring the bill in the House.

Congress has a pending bill on Stingrays, and California, Colorado, Wisconsin, and Virginia are among the 12 states that have passed laws addressing the technology, according to the National Conference of State Legislatures. Last week, Connecticut lawmakers sent the governor legislation that restricts the devices' use.

Amid the heightened scrutiny, authorities have cited instances in which the cell-tracking devices have been helpful. For example, Homeland Security Assistant Secretary Seth M. Stodder told a congressional committee in October that immigration officials used a Stingray to locate a 6-year-old girl who was being held hostage by smugglers in Arizona.

New York City police have used the technology extensively — more than 1,000 times since 2008, according to data released in February by the New York Civil Liberties Union — and have captured suspects in rapes, robberies and killings.

Baltimore police have used the technology at about 4,300 times since 2007 and hit a legal snag last month when a Baltimore judge dismissed key evidence in a murder case because it was obtained by using a Stingray. The ruling came weeks after a Maryland appeals court issued an opinion in a separate case saying evidence obtained using a Stingray violated constitutional protections against unreasonable searches and seizures.

Critics of the devices also worry that if there are no limits on how long the gathered data is stored, law enforcement can build databases that track individuals' patterns of behavior, like where someone attends political meetings, what doctors they see or what churches they attend.

"You can learn an enormous amount about a person," said Chad Marlow, advocacy and policy counsel for the American Civil Liberties Union in New York.