A key U.S. spy agency overstepped legal limits in intercepting private e-mail messages and phone calls, Justice Department officials said Thursday, as a top lawmaker called for a probe.
The National Security Agency (NSA), an important intelligence-gathering arm of America's vast espionage network, undertook the eavesdropping of US citizens' electronic communications in a bid to thwart global terrorism.
But the agency exceeded the authority Congress has laid out, U.S. officials said, adding the problems, which have since been corrected, were detected during "routine oversight" of the domestic eavesdropping program.
Sen. Dianne Feinstein, who heads the Senate Intelligence Committee, said the allegations are serious and warrant congressional investigation.
"These are serious allegations and we will make sure we get the facts," the Democratic lawmaker said, vowing to convene hearings soon.
Federal justice authorities said the problem has been rectified.
"The Department of Justice . . . took comprehensive steps to correct the situation and bring the program into compliance," said a statement from the Justice Department
The eavesdropping program was suspended until the fixes were in place.
"The Justice Department takes its national security oversight responsibilities seriously, and works diligently to ensure that surveillance under established legal authorities complies with the nation's laws, regulations and policies, including those designed to protect privacy interests and civil liberties," the agency said.
In a separate statement, the NSA said Thursday: "Our intelligence operations, including programs for collection and analysis, are in strict accordance with U.S. laws and regulations" as well as provisions of the Foreign Intelligence Surveillance Act, which governs espionage activities.
Because of the classified nature of the NSA's work, details about the precise nature of the violation were not provided.
News reports citing official sources said the NSA overreach had been inadvertent and stemmed from ambiguities in new legislation regulating the government's wiretapping powers.
The controversy is only the latest of many involving the warrantless wiretap program.
After the Sept. 11, 2001, terror attacks, former President George W. Bush authorized the NSA to monitor international phone calls, e-mails and other electronic communications without court authorization when at least one party was suspected of supporting or engaging in terrorist activities.
The former U.S. administration had asserted that it had the power to authorize domestic eavesdropping without court oversight.
But revelations in 2005 about the agency's domestic espionage efforts sparked an outcry from civil liberties groups, as well as from some U.S. lawmakers.
Congress approved legislation last year stating that the targets of the eavesdropping had to be "reasonably believed" to be outside the United States and stating that the NSA needed court approval to monitor the purely domestic communications of Americans who under suspicion.
But other violations have also come to light, the Times reported, including the agency's efforts to wiretap a member of Congress without court approval, while on an overseas trip.
The civil liberties community called on Congress to clamp down on NSA activities.
"Congress was repeatedly warned that this type of abuse would be the obvious outcome of passing the FISA Amendments Act," said Caroline Fredrickson, director of the ACLU Washington Legislative Office.
"It's time to ... restore the checks and balances of our surveillance system. Warrantless surveillance has no place in an America we can be proud of.
"These revelations make it clear that Congress must now make a commitment to rein in government surveillance," she said.
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