Department of Homeland Security says rogue cell-site simulators have been used in Washington, D.C., but the agency has no way to find them. Stingrays are used by most U.S. intelligence agencies and at least 25 police departments. The FCC formed a task force in 2014 to look into the unauthorized use of stingrays, but it never produced a report. The Associated Press pointed out that shutting down malicious stingrays would require expensive wireless network upgrades and could also lead to conflict with US intelligence and law enforcement”]