Canada's ultra-secret eavesdropping agency on Friday blasted the disclosure of its tradecraft, after it was reported the agency had tracked airline passengers connected to Wi-Fi services at airports.
As a trial run for the NSA and other foreign intelligence agencies, Canadian intelligence collected data from Canadian travelers who passed through major airports and connected to Wifi services and could then be tracked for days, CBC reports
Communications Security Establishment Canada said: "The unauthorized disclosure of tradecraft puts our techniques at risk of being less effective when addressing threats to Canada and Canadians."
On Thursday, the Canadian Broadcasting Corporation said documents leaked by fugitive NSA contractor Edward Snowden showed that the CSEC could follow the movements of people who passed through airports and connected to Wi-Fi systems with mobile phones, tablets and laptops.
The documents showed the agency could track the travellers for a week or more as they and their wireless devices showed up in other Wi-Fi "hot spots" in cities across Canada and beyond.
This included people visiting other airports, hotels, coffee shops and restaurants, libraries and ground transportation hubs and other places with public wireless Internet access.
Under Canadian law, the CSEC is prohibited from domestic spying.
But the agency said it is authorized to collect and analyze metadata -- the identifying data generated by calls from wireless devices such as called ID, telephone numbers and user location.
The leaked classified document was "a technical presentation between specialists exploring mathematical models built on everyday scenarios to identify and locate foreign terrorist threats."
According to the documents, older software took too long to locate targets to be useful. The new software cut the time from more than two hours to several seconds, in tests.
"It is important to note that no Canadian or foreign travellers were tracked. No Canadian communications were, or are, targeted, collected or used," the CSEC added.
Defense Minister Rob Nicholson meanwhile in Parliament said the CSEC is in "complete compliance with Canadian law."