The Electronic Frontier Foundation (EFF) is urging Facebook to answer claims that it allows undercover law-enforcement agents from Immigration and Customs Enforcement to operate under alias accounts, The Guardian reports. The watchdog organization claims ICE and other agencies are allowed to use fake accounts to carry out surveillance in defiance of the platform’s own privacy rules. “Facebook’s practice of taking down these individual accounts when they learn about them from the press (or from EFF) is insufficient to deter what we believe is a much larger iceberg beneath the surface,” according to a statement from EFF. “We often only discover the existence of law enforcement’s fake profiles months, if not years, after an investigation has concluded.”