America's secretive National Security Agency has defended its surveillance of cellphones globally, arguing that this is legally authorised under a sweeping US presidential order and such programmes have been used in some of the most dangerous parts of the world.
"This collection does not violate FISA (Foreign Intelligence Surveillance Act)," NSA spokeswoman Vanee Vines said in a statement.
It comes days after a Washington Post report said that NSA is collecting every day about five billion records on the whereabouts of cellphones around the world which includes both US and non-US citizens.
"It is not ubiquitous. NSA does not know and cannot track the location of every cell phone," she said. "This capability has been used in some of the most dangerous parts of the world, including war zones, where terrorists are actively planning to do harm to the nation," Vines said.
Without directly referring to The Washington Post story, the NSA official said this tracking is solely about foreign communication and does not involve tracking domestic cell phone.
"NSA tries to avoid the acquisition of US person communications during EO 12333 operations and also uses collection methodologies to comply with the restrictions in FISA," the official said.
Vines said the collection of the global cellphone location data is carried out under the White House order that governs all US espionage, known as Executive Order 12333.
"If EO 12333 collection results in the incidental acquisition of a communication to, from, or about a US person, we apply minimisation procedures and, depending on the specific circumstances, may also be required to destroy the record and report the incident to NSA's overseers," she said.
Arguing this particular NSA programme is outward-facing, Vines said the the agency doesn't intentionally acquire domestic information through this capability.
"FISA authorisation would be required for the intentional collection of domestic metadata. This activity is centred on overseas locations," she said.
The Washington Post based its report on the classified documents obtained from former CIA contractor and whistleblower Edward Snowden.
Noting that the NSA has no reason to suspect that movements of the overwhelming majority of cellphone users would be relevant to national security, the daily said, the agency collects locations in bulk because its most powerful analytic tools - known collectively as 'Co-Traveler' - allow it to look for unknown associates of known intelligence targets by tracking people whose movements intersect.
