especially on a government level. >> a few years ago deputy attorney sally yates said cell site simulators, sting rays are a critical tool for us finding fugitives and kidnapping victims and drug cases. still, she also acknowledged the need for restraint. the american civil liberties union said law enforcement agencies in at least 25 states and d.c. have sting rays. and the aclu argues their use often constitutes a type of illegal search and invasion of privacy with innocent people and their phones swept up in the electronic net. >> so, that's what these devices are and that's what they do. but still unanswered, who has been using them in the nation's capital. is it a foreign government, terrorist, some super secret police operation? homeland security either doesn't know or isn't letting on, but the confirmation that someone has been snooping with these things is setting off alarm