https://www.theregister.co.uk/2018/04/09/fcc_stingrays_fake_cellphone_towers/

Senior Congressmen have demanded "immediate action" over mysterious fake cell phone towers in Washington DC that they worry could be being operated by foreign governments.

House Reps Frank Pallone (D-NJ), Eliot Engel (D-NY) and Bennie Thompson (D-MS) this month sent a letter to Ajit Pai – the head of America's comms watchdog, the FCC – asking him to "address the prevalence of what could be hostile, foreign cell-site simulators, or Stingrays, surveilling Americans in the nation’s Capital."