FBI spokesman Christopher Allen says that the US Federal Bureau of Investigation follows the US Attorney General Guidelines when using Stingray cellphone tracking devices.

WASHINGTON (Sputnik) — The US Federal Bureau of Investigation (FBI) follows the US Attorney General Guidelines when using Stingray cellphone tracking devices, FBI spokesman Christopher Allen told Sputnik.

“In utilizing this equipment and data, the FBI conducts all investigations in accordance with the Attorney General Guidelines and the FBI's Domestic Investigations and Operations Guide,” Allen said on Tuesday.

On May 3, 2015, the American Civil Liberties Union Attorney Nathan Wessler said that the FBI and other US law enforcement agencies have been secretly using cellphone tracking equipment, which violates the Fourth Amendment to the US Constitution that prohibits searches without a warrant.

Wessler noted, however, that FBI agents have lately started receiving search warrants from US judges to use the devices.

Meanwhile, local media reported on Sunday that US mobile service providers such as Verizon Wireless and AT&T have seen a surge in emergency law enforcement requests for mobile phone tracking.

Allen argued that the mobile companies’ data shows requests were made from various US law enforcement agencies and the overall increase is not specific to the FBI.

Stingray phone trackers simulate cell phone towers to receive mobile phones unique identifying information. They have been developed by the US telecommunications company Harris Corporation to enable the US military and intelligence to precisely locate individuals’ cell phones.