Brazilian President Dilma Rousseff accused the Ottawa-based Communications Security Establishment Canada of engaging in industrial espionage.
Foreign Minister Luiz Alberto Figueiredo summoned the Canadian ambassador in the capital of Brasilia to "transmit the indignation of the Brazilian government and demand explanations," the Foreign Ministry said in a statement.
The accusations aired on Brazil's Globo television network also prompted questions from Canadian intelligence experts about exactly what the spy service should be doing and how much Canadians should be told of its priorities.
The television report said the metadata — or indexing details — of phone calls and emails from and to the ministry were targeted by the Canadian agency to map the ministry's communications.
The report was based on documents leaked by Edward Snowden, a former contractor with the National Security Agency — CSEC's American counterpart.
Snowden provided classified presentation slides from June describing an operation labelled Olympia that apparently involved CSEC capabilities known as "Advanced Network Tradecraft."
The slides map out communications between Brazil, Peru, Ecuador, Venezuela, Britain, Poland and Singapore.
They also suggest CSEC was working with the NSA's exclusive "Tailored Access Operations" division on setting up a "Man on the Side" operation — a kind of fake digital front that would allow the spy services to access valuable details.
Canadian officials were uniformly tight-lipped.
A spokesman for Prime Minister Stephen Harper would neither confirm nor deny the allegations when asked to respond to the report late Sunday night.
CSEC said it "does not comment on foreign intelligence gathering activities." Defence Minister Rob Nicholson, the cabinet member responsible for CSEC, said much the same thing.
"I don't comment, nor do we comment, on foreign intelligence gathering activities," Nicholson said.
"That being said, Canada does have a strong and ever-expanding bilateral relationship with Brazil and we look forward to continuing that collaboration and friendship."
During Monday's meeting, Figueiredo expressed "the government's repudiation of this serious and unacceptable violation of national sovereignty and the rights of people and companies," the Foreign Ministry statement said.
CSEC, with headquarters ringed by tall fencing in Ottawa's south end, monitors foreign computer, satellite, radio and telephone traffic for intelligence of interest to Canada.
It has a staff of more than 2,000 — including skilled mathematicians, linguists and computer whizzes — and a budget of about $400 million. It plans to move to elaborate new facilities in Ottawa's east end next to Canada's domestic spy agency.
Earlier documents leaked by Snowden suggest Canada helped the United States and Britain spy on participants at the London G20 summit four years ago. Britain's Guardian newspaper published presentation slides describing the operation, including one featuring the CSEC emblem.
Federal documents say that in 2011-12 the CSEC's priorities included a focus on Canada's mission in Afghanistan, proliferation of weapons of mass destruction, foreign espionage and interference, and the federal government's northern Canada strategy.
The revelations beg questions about CSEC's interest in Brazil as opposed to other priorities, said Wesley Wark, a visiting professor at the University of Ottawa's graduate school of public and international affairs.
"We've never historically devoted a lot of resources to economic intelligence gathering," he said. "It's not clear that we have a lot of resources to devote to that. We've never had any kind of public debate about whether that's a good way to use intelligence agencies."
Wark said he would be surprised if economic intelligence had indeed become a CSEC focus. "Because I think there's just too much else out there in the world to pay that they'd have to pay attention to."
The government should be clear about what kinds of economic topics might be considered legitimate foreign intelligence targets, said long-time CSEC watcher Bill Robinson.
"I think it would be reasonable for the government to lay out that kind of priority."
Following the television report, Rousseff instructed Mines Minister Edison Lobao to beef up the ministry's data protection systems.
Globo previously reported that the communications of Rousseff herself, and also state-run oil company Petrobras, were targeted by NSA spying.
The fallout over the spy programs led Rousseff last month to cancel a planned visit to the United States.
Speaking last month to the United Nations General Assembly, Rousseff called for international regulations that would govern data privacy and limit espionage programs targeting the Internet.
— With files from The Associated Press
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